Faculty Profiles - KIWA Toshihiko

J-GLOBAL

Nondestructive Evaluation of Continuous Welded Rails using Unsaturated AC Flux Leakage Measurements with a Gradiometer

林実, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2020 2020

Corrosion Detection of Reinforcing Bar Using Magnetic Flux Leakage Testing

川上太聖, 林実, 堺健司, 紀和利彦, 塚田啓二

電磁力関連のダイナミクスシンポジウム講演論文集 32nd 2020

Nondestructive Evaluation of Copper-alloy-casting Using Eddy Current Testing

志垣一也, 紀和利彦, 塚田啓二, 堺健司

電磁力関連のダイナミクスシンポジウム講演論文集 32nd 2020

Measurement of concentration of histamine in buffer solution using Terahertz Chemical Microscope for allergy screening

佐藤孝祐, 飯田将弘, 葭田勇一, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 67th 2020

Evaluation method of penetration speed of cosmetic liquid into skins using terahertz technology

紀和利彦

コスメトロジー研究報告 28 2020

Highly sensitive magnetic measurement systems using superconducting devices and their applications

塚田啓二, 堺健司, 紀和利彦

応用物理学会春季学術講演会講演予稿集(CD-ROM) 67th 2020

極低周波渦電流探傷法による錆で覆われた鋼材の板厚評価

富岡卓哉, 若林俊輝, 堺健司, 紀和利彦, 塚田啓二, 武藤秀人, 藤野陽三

電気学会全国大会講演論文集(CD-ROM) 2019 2019

磁気計測によるアルミニウム合金と鋼の溶接接合の評価

小部寛斗, 合田悠斗, 平田哲朗, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2019 2019

不飽和交流漏洩磁束法を用いた鉄鋼構造物の亀裂形状の推定

齊藤大介, 林実, 中村喜浩, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2019 2019

SQUID磁気免疫検査における磁気を用いた抗原抗体反応の時間短縮

平松文太, 神野克也, 綱島健太, 竹内駿, 藤元佳与, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2019 2019

テラヘルツ波ケミカル顕微鏡を用いた生体関連物質評価法 Reviewed

紀和利彦, 神谷樹, 飯田将弘, 井上博文, 堺健司, 豊岡伸一, 塚田啓二

日本レーザー医学会誌 39 ( 4 ) 341 - 346 2019

レーザー励起テラヘルツ波を用いた二次電池電極非破壊検査装置の開発

紀和利彦, 寺西貴志

山陽技術雑誌 67 2019

テラヘルツ波ケミカル顕微鏡による微小量溶液中イオン濃度計測

紀和利彦, 前野佑貴, 眞鼻敦也, AHMED Feroz, 堺健司, 塚田啓二

分析化学討論会講演要旨集 79th 2019

テラヘルツ波ケミカル顕微鏡を用いたin-situリチウムイオン電池評価法

紀和利彦, 秋和佑季, 寺西貴志, 秋和佑季, 能勢秀俊, 小林正樹, 堺健司, 塚田啓二

シンポジウムテラヘルツ科学の最先端講演要旨集 2019 2019

磁気免疫検査装置における溶媒による磁気ナノ粒子の磁気特性への影響

平松文太, 神野克也, 綱島健太, 藤元佳与, 堺健司, 紀和利彦, SAARI Mohd Mawardi Bin, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 70th 2019

光触媒のサブピコ秒電位変化の計測実現

紀和利彦

岡山工学振興会ニュース ( 115 ) 2019

極低周波渦電流探傷法による地際腐食検出性能の向上

若林俊輝, 富岡卓哉, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 22nd 2019

不飽和交流漏洩磁束法による鉄鋼構造物の溶接部欠陥信号の判別

林実, 斉藤大介, 中村喜浩, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 22nd 2019

微小金属欠陥が検出可能な磁気センサプローブの開発

小部寛斗, 合田悠斗, 神原匠, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 70th 2019

Thickness measurement of severely corroded steel structure using extremely low-frequency eddy current testing

齊藤大介, 林実, 若林俊輝, 富岡卓哉, 堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会秋季講演大会講演概要集 2019 2019

Evaluation of quenched area at the edge of steel plate using eddy current testing

堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会秋季講演大会講演概要集 2019 2019

None-Destructive Evaluation of Electrodes of Rechargeable Batteries by Terahertz Technology

紀和利彦, 藤原健太郎, 秋和佑希, 吉川祐未, 寺西貴志, 能勢秀俊, 小林正樹, 堺健司, 塚田啓二

レーザー研究 47 ( 1 ) 2019

Optimization of Pt ultra-thin film pattern for hydrogen sensor

合田悠斗, 平田哲朗, 堺健司, 紀和利彦, 近藤健二, 高橋琢哉, 上田尚宏, 塚田啓二

センサ・マイクロマシンと応用システムシンポジウム(CD-ROM) 35th 2018

極低周波渦電流探傷法によるチタン下の鋼材の板厚評価

富岡卓哉, 合田剛士, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2018 2018

TMRセンサを用いた鉄鋼材の亀裂検出

林実, 中村喜浩, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 21st 2018

極低周波渦電流探傷法による鉄鋼構造物の地際腐食検査

若林俊輝, 富岡卓哉, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 21st 2018

SQUID磁気免疫検査装置におけるC反応性タンパクの高感度検出

綱島健太, 神野克也, 竹内駿, 福田行治郎, 藤元佳与, 柴倉美砂子, 堺健司, 紀和利彦, 圓福敬二, 塚田啓二

電磁力関連のダイナミクスシンポジウム講演論文集 30th 2018

エネルギー輸送の違いから見たカーボンナノチューブの通電加熱の効果

中條大樹, 井上寛隆, 黒田泰平, 森本大我, 林拓磨, 徳永知春, 池田直, 横谷尚睦, 藤森和博, 羽田真毅, 西川亘, 山下善文, 紀和利彦, 林靖彦

応用物理学会春季学術講演会講演予稿集(CD-ROM) 65th 2018

テラヘルツ波飛行時間法を用いた皮膚組織への化粧水浸透評価

黒田泰平, 森本大我, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 65th 2018

グラジオメータを用いた不飽和交流磁束漏洩法によるき裂検出性能

中村喜浩, 林実, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2018 2018

SQUID磁気免疫検査装置における磁気マーカを用いたアビジン-ビオチン結合反応の基礎評価

神野克也, 綱島健太, 竹内駿, 藤元佳与, 堺健司, 紀和利彦, 圓福敬二, 塚田啓二

電磁力関連のダイナミクスシンポジウム講演論文集 30th 2018

超電導薄膜フォーカス板を用いた交流駆動法による磁気抵抗素子の高感度化

合田悠斗, 平田哲朗, 堺健司, 紀和利彦, 塚田啓二

電磁力関連のダイナミクスシンポジウム講演論文集 30th 2018

テラヘルツ技術の生体関連試料への応用

紀和利彦

オレオサイエンス 18 ( 9 ) 2018

不飽和交流漏洩磁束法による鉄鋼構造物の亀裂検出と表示方法

林実, 齊藤大介, 中村喜浩, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 69th 2018

2次微分検出コイルを用いた鉄鋼構造物の高リフトオフき裂検査法の開発

合田悠斗, 平田哲朗, 堺健司, 紀和利彦, 塚本晃, 田辺圭一, 塚田啓二

日本非破壊検査協会秋季講演大会講演概要集 2018 2018

磁気ナノ粒子を用いたCRPの磁気免疫分析方法

竹内駿, 神野克也, 綱島健太, 藤元佳与, 堺健司, 紀和利彦, 塚田啓二, 圓福敬二

低温工学・超電導学会講演概要集 96th 2018

超伝導コイルと磁気センサを用いた非破壊検査用広周波数帯域磁場検出器の開発

平田哲朗, 合田悠斗, 堺健司, 紀和利彦, 安達成司, 塚本晃, 田辺圭一, 塚田啓二

低温工学・超電導学会講演概要集 96th 2018

トンネル磁気抵抗センサを用いた金属材の微小欠陥の検出

神原匠, 堺健司, 紀和利彦, 塚田啓二, 鈴木雄太

日本磁気学会学術講演概要集 42nd 2018

マルチチャンネル磁気抵抗センサを用いた鉄鋼構造物の亀裂検出

林実, 中村喜浩, 堺健司, 紀和利彦, 塚田啓二

日本磁気学会学術講演概要集 42nd 2018

HTS-SQUIDを用いた磁場計測装置による局所領域電気化学インピーダンスの評価

堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 79th 2018

Development of non-destructive testing system using HTS-coil and magnetic sensor for high lift-off crack detection

平田哲朗, 合田悠斗, 堺健司, 紀和利彦, 安達成司, 塚本晃, 田辺圭一, 塚田啓二

MAGDAコンファレンス講演論文集 27th 2018

Detection of inner cracks in thick steel plates using non-saturated AC magnetic flux leakage testing with a magnetic resistance gradiometer

K. Tsukada, Y. Majima, Y. Nakamura, T. Yasugi, K. Sakai, T. Kiwa

2017 IEEE International Magnetics Conference, INTERMAG 2017 53 ( 11 ) 2553 - 2558 2017.8

Magnetic AC Impedance Analysis Method Using High-Tc SQUID Based Magnetic Measurement System

Kenji Sakai, Tsubasa Kizu, Toshihiko Kiwa, Keiji Tsukada

IEEE Transactions on Applied Superconductivity 27 ( 4 ) 274 - 282 2017.6

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

© 2016 IEEE. A new ac impedance analysis method that uses magnetic measurements was demonstrated. The magnetic field generated from the current flowing in the sample was detected by changing the frequency of the applied voltage. To detect the generated small magnetic field, a high-temperature superconductor superconducting quantum interference device (HTS-SQUID) based magnetic measurement system was developed. The developed system could detect the magnetic field without a change in the intensity and phase in the frequency range of 1 Hz to 10 kHz. In this frequency range, the spectrum correlated with the ac impedance of the electric circuit was obtained by measuring the magnetic field from the current in the circuit. Moreover, dye-sensitized solar cells with counter electrodes of different catalysis materials were prepared, and the magnetic field from the solar cell was measured. The Cole-Cole plot of the magnetic field correlated with the ac impedance measured by a conventional method, and the difference in the shape of Cole-Cole plot was explained using the equivalent circuit analysis of the dye-sensitized solar cell. Therefore, it was clarified that is possible to obtain the spectrum correlated with ac impedance using magnetic measurements.

DOI： 10.1109/TASC.2016.2631426

High-Resolution Laser-Assisted Magnetic Nanoparticle Imaging Using a High-T<inf>C</inf> SQUID Magnetometer

Toshihiko Kiwa, Koji Morita, Yasuaki Matsunaga, Mohd Mawardi Saari, Kenji Sakai, Keiji Tsukada

IEEE Transactions on Applied Superconductivity 27 ( 4 ) 1108 - 1114 2017.6

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

© 2017 IEEE. A new type of magnetic nanoparticle imaging (MPI) system has been proposed and developed. The spatial resolution of MPI systems is generally determined and limited by the size of the magnetic sensors used and the magnetic properties of the nanoparticles detected. Here, high-resolution imaging of magnetic particles was realized by combining the MPI system with a high-TC SQUID magnetometer and laser scanning system. The spatial resolution of this system was not determined by the properties of the magnetic nanoparticles but was determined by the laser spot size focused on samples. Thus, the higher spatial resolution imparted by conventional MPI systems could be expected. As a demonstration of the imaging system, two cylindrical containers filled with magnetic particles solutions were fabricated and measured. Although the containers were spaced only 2 mm apart, they could be clearly distinguished by the obtained signals. A knife-edge analysis was also applied to the obtained signals, and the spatial resolution of our system was estimated to be approximately 0.9 mm.

DOI： 10.1109/TASC.2017.2656118

Magnetic characteristics measurements of ethanol-water mixtures using a hybrid-type high-temperature superconducting quantum-interference device magnetometer

Keiji Tsukada, Yasuaki Matsunaga, Ryota Isshiki, Yuta Nakamura, Kenji Sakai, Toshihiko Kiwa

AIP Advances 7 ( 5 ) 158 - 162 2017.5

Language：English Publisher：AMER INST PHYSICS

© 2017 Author(s). The magnetic characteristics of ethanol-water mixtures were investigated using our newly developed hybrid-type magnetometer based on a high-temperature superconducting quantum-interference device. The magnetization (M-H) curves of ethanol-water mixtures show good diamagnetic characteristics. The magnetic moments of the mixture show ethanol concentration dependence. However, the variation in magnetic moment differs from the characteristics expected by considering the magnetic moment ratio between water and ethanol, and volume-reduction rate. It showed two decrement regions separated at approximately 50-60% concentration values. It is also observed that the concentration dependence of the magnetic moment measured using the sample vibration method under a uniform magnetic field and that by the sample rotation method showed slightly different characteristics. These anomalies are attributed to the formation of clustered structures in the mixture.

DOI： 10.1063/1.4973950

Absolute-magnetic-field measurement using nanogranular in-gap magnetic sensor with second-harmonic and liquid-nitrogen-temperature operation

Keiji Tsukada, Takuya Yasugi, Yatsuse Majima, Kenji Sakai, Toshihiko Kiwa

AIP Advances 7 ( 5 ) 1257 - 1264 2017.5

Language：English Publisher：AMER INST PHYSICS

© 2017 Author(s). To detect the absolute magnetic field, such as the earth’s magnetic field, a linear magnetic response, a zero point, and thermal stability are required. We thus propose an operating method and sensor probe consisting of a nanogranular in-gap magnetic sensor (GIGS), an operational amplifier integrated circuit, and a modulation coil. The sensor probe was operated in second-harmonic mode at a liquid-nitrogen (Liq. N2) temperature. When an AC magnetic field was applied to GIGS, the second-harmonic signal was generated and modulated by the outer magnetic field to be measured. After lock-in detection, the modulated output signal showed good linearity and a zero point. Moreover, higher sensitivity and low noise with low thermal fluctuation was obtained by the cooling at Liq. N2 temperature.

DOI： 10.1063/1.4978217

Magnetic method for measuring moisture content using diamagnetic characteristics of water

Tsukada Keiji, Matsunaga Yasuaki, Nakamura Yuta, Isshiki Ryota, Fujimoto Kayo, Sakai Kenji, Kiwa Toshihiko

Measurement Science and Technology 28 ( 1 ) 3477 - 3487 2017.1

Language：English Publisher：IOP PUBLISHING LTD

© 2016 IOP Publishing Ltd. Moisture content measurements of rice kernels and soil are important for agriculture. Therefore, in this study, a new measurement method using the diamagnetic characteristics of water was developed for measurements of the moisture content of rice kernels and soil. The magnetic characteristics of the samples were determined using a magnetometer developed by us based on a superconducting quantum interference device. Because of the diamagnetic characteristics of water, the susceptibility of rice kernels became more negative with increasing moisture content. In the case of soil, which is a mixture of diamagnetic and ferromagnetic materials, a second-harmonic detection method using AC with DC bias magnetic field was applied to reduce the influence of the ferromagnetic signal. The intensity of the second-harmonic signal of a soil was determined to be proportional to its moisture content.

DOI： 10.1088/1361-6501/28/1/014010

HTS-SQUID磁気測定装置を用いたエタノール水溶液の磁気特性評価

中村勇太, 松永恭暁, 一色良太, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 64th 2017

多重周波数印加磁場を用いた極低周波渦電流探傷検査法による鋼板裏面欠陥検出

合田剛士, 芳賀勇太, 富岡卓哉, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2017 2017

交流変調を用いたTMRセンサの駆動法

中村喜浩, 八杉拓也, 馬島八世, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2017 2017

テラヘルツ波飛行時間測定法による鳥皮膚組織への化粧液浸透評価(II)

森本大我, 有澤翼, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 64th 2017

テラヘルツ波ケミカル顕微鏡を用いた電極評価法の検討

藤原健太郎, 川上祐輝, 日野佑次, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 20th 2017

Pt超薄膜を用いたブリッジ型水素センサの開発

天野薫, 古川遼, 井並祥太, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2017 2017

HTS-SQUID磁気計測装置を用いた磁気ナノ粒子水溶液の溶媒粘度による磁気特性変化評価

一色良太, 中村勇太, 松永恭暁, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 64th 2017

HTS-SQUIDを用いた電流が作る磁場の周波数特性測定と交流インピーダンスとの相関性

木津翼, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 64th 2017

高温超伝導SQUIDを用いた磁気計測による電気化学インピーダンスの推定

堺健司, 木津翼, 紀和利彦, 塚田啓二

電磁力関連のダイナミクスシンポジウム講演論文集 29th 2017

不飽和交流磁束漏洩法(USAC-MFL)による鉄板裏面き裂の検出

中村喜浩, 富岡卓哉, 馬島八世, 合田剛士, 堺健司, 紀和利彦, 塚田啓二

電磁力関連のダイナミクスシンポジウム講演論文集 29th 2017

極低周波渦電流探傷法の高速化

富岡卓哉, 合田剛士, 堺健司, 紀和利彦, 塚田啓二

電磁力関連のダイナミクスシンポジウム講演論文集 29th 2017

低周波磁場を用いた酸化膜付き鋼板の焼入れ状態評価

堺健司, 伊藤嵩展, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 20th 2017

磁気スペクトル解析を用いた極低周波渦電流探傷法による腐食鋼構造物の板厚検査

富岡卓哉, 合田剛士, 芳賀勇太, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 20th 2017

不飽和交流漏洩磁束探傷法の開発と鋼板のき裂検出応用

馬島八世, 八杉拓也, 中村喜浩, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 20th 2017

超伝導薄膜フォーカス板を用いた磁気抵抗素子の応答特性

平田哲朗, 中村喜浩, 馬島八世, 天野薫, 堺健司, 紀和利彦, 塚田啓二

低温工学・超電導学会講演概要集 94th 2017

磁気ナノ粒子の溶媒による磁気的挙動変化の高感度測定

竹内駿, 平田哲朗, 一色良太, 中村勇太, 藤元佳与, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2017 2017

極低周波渦電流探傷法によるチタンライニング下の鋼材の板厚評価

富岡卓哉, 合田剛士, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 68th 2017

不飽和交流磁束漏洩法によるき裂検出性能

中村喜浩, 馬島八世, SONG NANNAN, 堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会秋季講演大会講演概要集 2017 2017

テラヘルツ波ケミカル顕微鏡を用いた電気化学イメージングシステムの開発

藤原健太郎, 川上祐輝, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 78th 2017

HTS-SQUIDを用いた磁気ナノ粒子水溶液の異なる溶媒による磁気特性変化の高感度解析

一色良太, 中村勇太, 竹内駿, 平田哲朗, 藤元佳与, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 78th 2017

超伝導薄膜フォーカス板を用いた磁気抵抗素子の応答特性

平田哲朗, 中村喜浩, 馬島八世, 天野薫, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 78th 2017

超薄膜白金を用いたブリッジ型水素センサ

天野薫, 古川遼, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2017 2017

HTS-SQUID磁気特性計測装置の反磁性サンプル回転計測法の高感度化

中村勇太, 竹内駿, 平田哲郎, 一色良太, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 68th 2017

HTS-SQUIDを用いたレーザーアシスト磁気ナノ粒子イメージングの基礎検討

竹内駿, 平田哲朗, 一色良太, 中村勇太, 堺健司, 紀和利彦, 塚田啓二

低温工学・超電導学会講演概要集 94th 2017

Current distribution evaluation of dye-sensitized solar cell using HTS-SQUID-based magnetic measurement system

Kenji Sakai, Kohei Tanaka, Toshihiko Kiwa, Keiji Tsukada

Physica C: Superconductivity and its Applications 530 113 - 116 2016.11

Language：English Publisher：ELSEVIER SCIENCE BV

© 2016 Elsevier B.V. The current flowing inside a dye-sensitized solar cell (DSSC) was measured using a high-temperature superconductor superconducting quantum interference device (HTS-SQUID)-based magnetic measurement system. Further, a new evaluation method of the DSSC, which is difficult to measure using the conventional method, was investigated to improve the characteristics of the DSSC. The tangential components of the magnetic field generated from the DSSC were measured using two HTS-SQUIDs, and the intensity and direction related to the electrical current were obtained by the measured magnetic field. The DSSCs prepared with different dyes and catalytic substances showed different current-intensity mapping. The current direction was different for the DSSC with low performance. In addition, the current flowing in the ITO layer of the ITO glass substrate was also measured and the results confirmed that it had uniform distribution. These results show that the current mapping and the direction of the electrical current depend on the internal factors of the DSSC, and the detection of the magnetic field distribution generated from it is expected to lead to its new evaluation method.

DOI： 10.1016/j.physc.2016.04.002

Detection of Inner Corrosion of Steel Construction Using Magnetic Resistance Sensor and Magnetic Spectroscopy Analysis

Keiji Tsukada, Yuta Haga, Koji Morita, Nannan Song, Kenji Sakai, Toshihiko Kiwa, Weiying Cheng

IEEE Transactions on Magnetics 52 ( 7 ) 2016.7

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

© 2016 IEEE. The detection of the inner corrosion of steel construction, specifically backside corrosion of a steel plate, is highly demanded to maintain safety. Eddy-current testing (ECT) is widely used as a nondestructive testing and an evaluation method for detecting surface and subsurface flaws. However, the ECT is usually applied to non-ferromagnetic materials, but has difficulties when applied to ferromagnetic materials with high permeability, since the skin depth is smaller, and the signal-to-noise ratio (SNR) decreases due to magnetic flux fluctuation. In this paper, we developed a magnetic probe using an anisotropic magnetic resistance (AMR) sensor with the sensitivity of 1 nT/ Hz that can detect inner corrosion at extremely low frequency. We also developed an analysis method using magnetic spectroscopy to delete the magnetic flux fluctuation. To improve the SNR of the detected signal, a small cancellation coil around the AMR sensor canceled the applied magnetic field directly coupled to the sensor. The frequency of the applied magnetic field ranged from 1 Hz to 1 kHz. The sensor output at each frequency was lock-in detected. The weak ac magnetic field was applied to the initial permeability region of the magnetization curve. The obtained magnetic vector signal consisting of a real part and an imaginary part at each frequency was plotted as magnetic spectroscopy, and the magnetic component of the eddy current and the magnetic component of the magnetization of the steel were separated. By using the magnetic component of the eddy current, the thickness of an iron steel plate thinner than 16 mm could be measured. Moreover, the shape of the back-side corrosion was determined by scanning with the magnetic probe.

DOI： 10.1109/TMAG.2016.2530851

Hybrid Type HTS-SQUID Magnetometer with Vibrating and Rotating Sample

Keiji Tsukada, Koji Morita, Yasuaki Matsunaga, Mohd Mawardi Saari, Kenji Sakai, Toshihiko Kiwa

IEEE Transactions on Applied Superconductivity 26 ( 3 ) 2016.4

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

© 2016 IEEE. Highly sensitive measurement of the very weak magnetic characteristics of magnetic particles in solution or of a solution itself is required for applications, such as biomedical examinations. In this paper, higher sensitivity and additional performance with relaxation measurement and harmonic signal detection were achieved by an improvement of the driving mechanism and the high-resolution electric magnet, and optimization of the superconducting quantum interference device (SQUID) detection unit. A servomotor was used for sample vibration and rotation with precise control and high speed. For detection of the M-H characteristics, the sample was vibrated under the magnetic field in the electromagnet. For measuring the relaxation of the magnetization, the sample was rotated. A first-order differential pickup coil with a normal conducting wire connected to the input coil of a higherature superconductor-SQUID was used to detect the magnetic signal from the sample. High-resolution measurement of the magnetic moment on the order of 10-11 A m2 was achieved with this system configuration. An ac magnetic field with a dc bias could then be applied to the sample for detection of the harmonic signal. The magnetic relaxation signal from the sample was measured by another of the same type of differential detection coil equipped outside of the electric magnet by rotating, instead of vibrating, the sample. The magnetization curve for a low concentration of iron nanoparticles with a superparamagnetic character in the solution was successfully measured using the developed magnetometer, and the relaxation phenomenon was also characterized.

DOI： 10.1109/TASC.2016.2531632

Label-free detection of low-molecular-weight samples using a terahertz chemical microscope

Takuya Kuwana, Masahiro Ogawa, Kenji Sakai, Toshihiko Kiwa, Keiji Tsukada

Applied Physics Express 9 ( 4 ) 2016.4

Language：English Publisher：IOP PUBLISHING LTD

© 2016 The Japan Society of Applied Physics. A terahertz chemical microscope (TCM) has been proposed and developed to visualize the distribution of biomolecular interactions on a sensing plate without any labels. In this study, the concanavalin A (Con A)-D-(+)-mannose (mannose) interaction was detected using the TCM with mannose applied as the analyte and Con A immobilized on the sensing plate. To demonstrate this interaction, the amplitude of terahertz pulses as a function of Con A-mannose interaction time, as well as the Con A-mannose coupling concentration, was evaluated. The results suggest that coupling kinetics may be evaluated using a TCM.

DOI： 10.7567/APEX.9.042401

Compact AC/DC Susceptometer Using a High-Temperature Superconducting Quantum Interference Device

Ryuki Takagi, Mohd Mawardi Saari, Kenji Sakai, Toshihiko Kiwa, Keiji Tsukada

Electronics and Communications in Japan 99 ( 3 ) 369 - 374 2016.3

Language：English Publisher：WILEY-BLACKWELL

© 2016 Wiley Periodicals, Inc. We developed a compact susceptometer employing a high-temperature superconductor (HTS) superconducting quantum interference device (SQUID) that can measure the M-H characteristics and the harmonic components induced in the ac magnetic field response from a sample. In the dc function for measuring M-H characteristics, the sample was vibrated in a dc magnetic field, and the secondary magnetic field generated from the sample was detected by a dc pickup coil. In the ac function for measuring harmonic components, the sample placed in an ac magnetic field, and the ac response was detected by an ac pickup coil. The pickup coil is connected in series with the input coil, which is inductively connected to the HTS-SQUID. A signal from the HTS-SQUID was transmitted to a lock-in amplifier and was analyzed as the intensity and phase of the measured magnetic field. In order to clarify the basic properties of the system, we measured the ac magnetic field response from a sample while varying the relative positions of the sample and the pickup coil, and the M-H characteristics while varying the dc bias magnetic field intensity. Furthermore, by analyzing the harmonic components of the ac/dc magnetic field response, the proposed system can measure magnetic field properties with high sensitivity and at high speed.

DOI： 10.1002/ecj.11779

Improvement of sensitivity of a compact magnetometer by using HTS-SQUID with rotating sample

Daichi Hamasaki, Naohiro Okamoto, Mohd Mawardi Saari, Kenji Sakai, Toshihiko Kiwa, Keiji Tsukada

Electrical Engineering in Japan (English translation of Denki Gakkai Ronbunshi) 194 ( 2 ) 9 - 14 2016.1

Language：English Publisher：WILEY

© 2015 Wiley Periodicals, Inc. We have improved a previously developed compact magnetometer using HTS-SQUID with a rotating sample. In the previous system, attenuation of the rotational speed had resulted in deformation of the averaged waveform signal, reducing the reproducibility of measurements. In this paper, we have used a better motor in order to decrease the attenuation of the rotational speed for precise averaging of the output signal and improvement of the signal-to-noise ratio. To improve sensitivity, we also optimized the pickup coil and compared the signal-to-noise ratio of circular and elliptical pickup coils having the same number of turns, resistance, and inductance. As a result, the signal-to-noise ratio was improved with high accuracy and the magnetometer showed a susceptibility sensitivity of 3.8× 10-9 emu.

DOI： 10.1002/eej.22732

Development of a Magnetic Phase Map for Analysis of the Internal Structure of a Spot Weld

Nannan Song, Keisyu Shiga, Kenji Sakai, Toshihiko Kiwa, Keiji Tsukada

Studies in Applied Electromagnetics and Mechanics 41 ( 41 ) 302 - 311 2016

Language：English Publisher：IOS PRESS

© 2016 The authors and IOS Press. All rights reserved. Resistance spot welding technologies are widely used in industry. We previously reported an analysis method for examining the strength of spot-welded parts with the eddy current test (ECT) by using a wide range of frequencies from high to low. However, liftoff has a non-negligible effect. Increasing the liftoff significantly decreases the magnetic field intensity for mapping. The magnetic field phase is not affected by changes in liftoff. The measured phase map of the magnetic field showed a good correlation with the results of the destructive shear test. In this paper, we report an analysis and imaging method for examining spot-welded parts based on the phase of a magnetic field by using a wide range of frequencies from high to low. With the magnetic phase map, the internal structure of a spot weld was visualized for easy understanding of the results of this method. Thus, this method can easily be applied to industrial production. This new method was validated through both experimental and simulation results.

DOI： 10.3233/978-1-61499-639-2-302

Chloride ion sensor using electrochemical impedance spectroscopy

Ryosuke Sugai, Kenji Sakai, Toshihiko Kiwa, Keiji Tsukada

IEEJ Transactions on Sensors and Micromachines 136 ( 4 ) 102 - 107 2016

Language：Japanese Publisher：Institute of Electrical Engineers of Japan

© 2016 The Institute of Electrical Engineers of Japan. An ion sensor of all solids type using Ag/AgCl standard electrode was previously reported. It was thought impedance measurement of chloride ion concentration instead of potentiometric measurement will be possible. In this study, chloride ion response characteristic in various solutions and influence of temperature were evaluated using Nyquist plot analysis.

DOI： 10.1541/ieejsmas.136.102

J-GLOBAL

特性が異なる色素増感型太陽電池のHTS-SQUIDを用いた磁場計測による電流特性分布評価

堺健司, 木津翼, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 77th 2016

電気化学インピーダンス法を用いた塩素イオンセンサ

菅井良祐, 堺健司, 紀和利彦, 塚田啓二

電気学会論文誌 E 136 ( 4 ) 2016

低周波磁場を用いた漏洩磁束探傷検査法による鋼板裏面の欠陥検出

合田剛士, 芳賀勇太, SONG Nannan, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 67th 2016

焼入れによる鋼板の材料特性変化と磁気的非破壊検査法による部分非焼入れ部の判別

堺健司, 伊藤嵩展, 紀和利彦, 塚田啓二

日本非破壊検査協会秋季講演大会講演概要集 2016 2016

磁気ナノ粒子水溶液の磁化特性計測による粒径分布解析

一色良太, 中村勇太, 松永恭暁, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2016 2016

白金薄膜の水素応答特性評価と水素センサへの応用

天野薫, 古川遼, 井並祥太, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2016 2016

交流変調駆動によるTMRセンサの磁気応答特性

八杉拓也, 馬島八世, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 67th 2016

交流変調法を用いた磁気センサ駆動の非破壊検査システムへの応用

馬島八世, 八杉拓也, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 67th 2016

低周波磁場ベクトルスペクトルを用いた鋼板の板厚検査

芳賀勇太, 合田剛士, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 67th 2016

条件が異なる焼入れ部の判別に向けた鋼板の焼入れ温度と磁場応答の関係

伊藤嵩展, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 67th 2016

インピーダンス法を用いた塩素センサ用Ag/AgCl電極の評価

天野薫, 菅井良祐, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2016 2016

渦電流分布の可視化による表面下欠陥位置及び形状の推定

馬島八世, 八杉拓也, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 19th 2016

地方創生,中国地方を元気に!4.[岡山発]テラヘルツ計測システム開発プロジェクト

紀和利彦

電子情報通信学会誌 99 ( 10 ) 2016

低周波渦電流探傷法を用いた金属内部欠陥検出法の開発

SONG Nannan, 馬島八世, 八杉拓也, 堺健司, 紀和利彦, 塚田啓二

日本磁気学会学術講演概要集 40th 2016

交流変調を用いたTMR磁気センサの駆動

馬島八世, 八杉拓也, 堺健司, 紀和利彦, 塚田啓二

日本磁気学会学術講演概要集 40th 2016

テラヘルツ波飛行時間測定法による鳥皮膚組織への化粧液浸透評価

有澤翼, 森本大我, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 77th 2016

磁気検査法による鋼材の疲労度評価に向けた材料特性評価と漏洩磁束分布との相関性

堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 19th 2016

低周波磁場スペクトルを用いた渦電流探傷検査法による鋼板の板厚評価

合田剛士, 芳賀勇太, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 19th 2016

テラヘルツ波ケミカル顕微鏡を用いた電池電極反応分布計測

紀和利彦, 堺健司, 塚田啓二

光アライアンス 27 ( 8 ) 2016

A terahertz chemical microscopy and applications for chemical sensors

紀和利彦

Chemical Sensors 32 ( 1 ) 2016

テラヘルツ波ケミカル顕微鏡を用いた微少量溶液pH計測

濱田輝, 秋宗広祐, ZHOU Y., 紀和利彦, 堺健二, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 63rd 2016

磁気を用いた高感度アルコール濃度計測に向けたSN比の向上

中村勇太, 松永恭暁, 一色良太, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2016 2016

テラヘルツ波ケミカル顕微鏡を用いたレクチン糖相互作用のリアルタイム計測

花岡侑樹, 桑名卓也, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2016 2016

超伝導コイルの磁場遮蔽特性を用いた非破壊検査

松永恭暁, 一色良太, 中村勇太, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2016 2016

超薄膜Pt水素センサの熱的安定性の向上と水素に対する温度特性

古川遼, 天野薫, 井並祥太, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2016 2016

HTS-SQUIDを用いた磁気ナノ粒子の基礎特性評価

一色良太, 中村勇太, 松永恭暁, 堺健司, 紀和利彦, 塚田啓二

低温工学・超電導学会講演概要集 93rd 2016

テラヘルツ波ケミカル顕微鏡を用いた電気化学反応計測法の開発

川上祐輝, 日野佑次, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2016 2016

超高感度磁気センサを用いた電流分布計測によるモジュール型色素増感型太陽電池の評価

木津翼, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2016 2016

テラヘルツ波ケミカル顕微鏡を用いた微少量溶液pHセンサの開発

ZHOU Y., 秋宗広祐, 濱田輝, 紀和利彦, 塚田啓二, 堺健司

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2016 2016

HTS-SQUIDを用いた高調波による砂の水分量計測

中村勇太, 松永恭暁, 一色良太, 堺健司, 紀和利彦, 塚田啓二

低温工学・超電導学会講演概要集 93rd 2016

超薄膜水素センサの安定性の改善

古川遼, 井並祥太, 菅井良祐, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2016 2016

交流変調によるMRセンサの駆動法

八杉拓也, 志賀啓秀, 馬島八世, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2016 2016

TiNを用いたPt超薄膜水素センサの熱的安定性改善

井並祥太, 古川遼, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 63rd 2016

高温超伝導コイルと一体化した磁気センサの非破壊検査応用

松永恭暁, 森田洪爾, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 63rd 2016

HTS-SQUIDと近赤外光を用いたMPIシステムによる皮膚下MNP検出の検討

森田洪爾, 松永恭暁, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 63rd 2016

低周波磁場ベクトルスペクトルによる腐食鋼板の厚み測定

芳賀勇太, 森田洪爾, 合田剛士, 伊藤嵩展, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2016 2016

Automatic scanning system for back-side defect of steel structure using magnetic flux leakage method

K. Sakai, K. Morita, Y. Haga, T. Kiwa, K. Inoue, K. Tsukada

2015 IEEE International Magnetics Conference, INTERMAG 2015 2015.7

Language：English Publishing type：Research paper, summary (international conference) Publisher：IEEE

© 2015 IEEE. Non-destructive evaluation (NDE) of steel structures, such as bridge and heavy machine, is important issue to ensure their safety and reliability. However, the conventional NDE methods for these structures require long inspection time and high cost because inspections are generally performed manually. Moreover, the measurement in high-place work is also required for the inspection of huge steel structure. Therefore, the measurement system should be compact and an automatically controllable measurement system is desirable. Considering these requirement, NDE using magnetic method is suitable because the measurement system is simple and non-contact measurement are possible [1]. In this study, an automatic scanning system which can move on a wall and ceiling of steel structure was developed. In addition, to demonstrate the developed system for practical measurement, back-side defect caused by corrosions generated in steel structures of cargo crane was measured.

DOI： 10.1109/INTMAG.2015.7157125

Impedance Evaluation of Hydrogen Sensor Using Ultrathin Platinum Film

Shuzo Takeichi, Yuki Ushita, Ryosuke Sugai, Kenji Sakai, Toshihiko Kiwa, Keiji Tsukada

40 ( 1 ) 62 - 72 2015

低周波磁場を用いた漏洩磁束探傷検査法による強磁性体材料の板厚評価

芳賀勇太, 森田洪爾, 堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会秋季講演大会講演概要集 2015 2015

TMRセンサ高調波信号を用いた非破壊検査システムの開発と画像化

八杉拓也, 志賀啓秀, 塚本有哉, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 18th 2015

自動走行システムを用いたコンテナクレーン鋼構造部の漏洩磁束探傷法による非破壊検査

堺健司, 森田洪爾, 芳賀勇太, 紀和利彦, 塚田啓二, 井上勝美

表面探傷シンポジウム講演論文集 18th 2015

AMRセンサアレイを用いた漏洩磁束探傷試験による鋼板の裏面欠陥検出

森田洪爾, 塚本有哉, 志賀啓秀, 芳賀勇太, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2015 2015

超薄膜Pt/Tiを用いたブリッジ型水素センサの開発

井並祥太, 牛田祐貴, 武市修蔵, 菅井良祐, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 62nd 2015

磁気センサアレイを用いた漏洩磁束法による裏面腐食欠陥検査

芳賀勇太, 森田洪爾, 堺健司, 紀和利彦, 塚田啓二

表面探傷シンポジウム講演論文集 18th 2015

テラヘルツ波ケミカル顕微鏡によるD-(+)-マンノースの非標識検出

小川真寛, 中村彰宏, 紀和利彦, 堺健司, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 62nd 2015

高温超伝導SQUIDを用いた磁化率計開発

紀和利彦, 堺健司, SAARI Mohd Mawardi, 塚田啓二

電子情報通信学会大会講演論文集(CD-ROM) 2015 2015

TMRセンサを用いた欠陥の渦電流探傷検査

志賀啓秀, 八杉拓也, 塚本有哉, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2015 2015

HTS-SQUIDを用いた高機能サンプル振動型磁化率計の開発

松永恭暁, SAARI Mohd Mawardi, 日下瞬, 森田洪爾, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 62nd 2015

SQUIDグラジオメータを用いた2ch.磁気計測システムの開発

田中洸平, 糟谷尚平, 石原優一, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2015 2015

テラヘルツ波の新時代テラヘルツ波ケミカル顕微鏡=新しい非標識バイオイセンシングツールの開発=

紀和利彦

光アライアンス 26 ( 1 ) 2015

超薄膜水素センサの安定性改善

井並祥太, 菅井良祐, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2015 2015

接線2成分磁場合成による電流分布の可視化と欠陥推定への利用

八杉拓也, 志賀啓秀, SONG Nannan, 堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会秋季講演大会講演概要集 2015 2015

鋼板における部分非焼入れ部の磁気的手法を用いた非破壊検査の検討

堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会秋季講演大会講演概要集 2015 2015

非破壊検査に向けた高温超伝導コイルの磁場応答評価

松永恭暁, SAARI Mohd Mawardi, 森田洪爾, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2015 2015

MPIの高空間分解能化へ向けた高調波比の応用

森田洪爾, SAARI Mohd Mawardi, 松永恭暁, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 76th 2015

HTS-SQUIDと複数の検出コイルを用いた試料回転型磁気応答計測システムの開発

渡部裕太, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 76th 2015

HTS-SQUIDグラジオメーターを用いた磁気計測システムによる色素増感型太陽電池の評価

堺健司, 田中洸平, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 76th 2015

HTS-SQUIDを用いたMPIシステムの赤外光による空間分解能向上の検討

森田洪爾, SAARI Mohd Mawardi, 松永恭暁, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 76th 2015

テラヘルツ波ケミカル顕微鏡を用いた液中イオンの同時検出

秋宗広祐, 大川裕貴, 紀和利彦, 堺健二, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 62nd 2015

テラヘルツ技術の最前線-光源と応用の最新動向-テラヘルツ波ケミカル顕微鏡の開発

紀和利彦, 堺健司, 塚田啓二

Optronics ( 405 ) 2015

テラヘルツ波ケミカル顕微鏡による生体関連物質相互作用検出

紀和利彦, 秋宗広祐, 周益, 堺健司, 塚田啓二

日本分析化学会年会講演要旨集 64th 2015

低周波磁場を用いた鋼板の厚み測定システムの開発

森田洪爾, 芳賀勇太, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 66th 2015

HTS-SQUIDを用いた電流分布測定による各種太陽電池の評価

田中洸平, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 66th 2015

Stabilization method for signal drifts in terahertz chemical microscopy. International journal

Toshihiko Kiwa, Kenji Sakai, Keiji Tsukada

Optics express 22 ( 2 ) 1330 - 5 2014.1

Language：English Publisher：OPTICAL SOC AMER

A stabilization method for signal drifts in terahertz chemical microscopy (TCM) due to unexpected chemical potential changes in sample solutions was proposed and developed. The sensing plate was separated into two areas: a detection area and a control area. The detection area radiated a THz pulse whose amplitude was related to both the chemical reactions in the sample solutions and unexpected potential changes. The THz pulse from the control area was related only to unexpected potential changes. In the proposed system, the THz pulse from each area was interfered and detected. By adjusting the timing of the positive peak of the THz pulse from the detection area and the negative peak of the THz pulse from the control area, we detected the difference in both peaks as the interference signal. Thus, the signal deviation of 390 when the environmental condition changes in the temperature range of 38 °C and the pH range of 8.33 was stabilized to be the signal deviation of 31. As the result, the TCM with stabilization method could detect the signal shift of 121 when the 275-nmol/L immunoglobulin G was immobilized on the sensing plate.

DOI： 10.1364/OE.22.001330

HTS-SQUIDを用いた電解質中イオン輸送の可視化

紀和利彦, 糟谷尚平, 宮崎真吾, 堺健司, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 61st 2014

Magnetic Relaxation Measurement Using HTS-SQUID Based Rotating Sample Magnetometer with High Sensitivity

堺健司, 岡本直大, 浜崎大地, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

電子情報通信学会技術研究報告 113 ( 401(SCE2013 35-57) ) 2014

HTS-SQUIDを用いた磁気応答計測システムの高感度化による水分量評価への応用

堺健司, 日下瞬, 岡本直大, 浜崎大地, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

電子情報通信学会大会講演論文集(CD-ROM) 2014 2014

トンネル型磁気抵抗素子を用いた裏面欠陥非破壊検査

塚本有哉, 志賀啓秀, 堺健司, 紀和利彦, 西川卓男, 塚田啓二

電磁力関連のダイナミクスシンポジウム講演論文集 26th 2014

渦電流探傷検査法を用いたスポット溶接の検査法の開発

志賀啓秀, 塚本有哉, SONG Nannan, 堺健司, 紀和利彦, 塚田啓二

電磁力関連のダイナミクスシンポジウム講演論文集 26th 2014

HTS-SQUIDを用いた小型AC/DC磁化率計の研究開発

森田洪爾, MOHD Mawardi, 高木竜輝, 石原優一, 日下瞬, 塚本有哉, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2014 2014

HTS-SQUIDグラジオメータを用いた太陽電池評価システムの開発

田中洸平, 宮崎真伍, 糟谷尚平, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集(CD-ROM) 2014 2014

高温超伝導SQUIDを用いた磁気計測システムの高精度化と水分量計測への応用

堺健司, 渡部裕太, 岡本直大, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

MAGDAコンファレンス講演論文集 23rd 2014

スポット溶接内部構造解析用3Dマップの開発

SONG Nannan, 塚本有哉, 志賀啓秀, 原田大地, 堺健司, 紀和利彦, CHENG Weiying, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2014 2014

磁場分布自動計測システムを用いた鋼材の疲労度評価の検討

堺健司, 秋山貴俊, 紀和利彦, 井上勝美, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2014 2014

漏洩磁束探傷法を用いた鋼構造部内部腐食の検出

堺健司, 秋山貴俊, 紀和利彦, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2014 2014

HTS-SQUIDを用いた電解質中イオン輸送の可視化(II)

紀和利彦, 田中洸平, 糟谷尚平, 堺健司, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 75th 2014

白金超薄膜を用いたブリッジ型水素センサ

牛田祐貴, 武市修蔵, 菅井良祐, 井波祥太, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 65th 2014

テラヘルツ波ケミカル顕微鏡による燃料電池の触媒反応解析

古礒和樹, 日下鉄也, 紀和利彦, 堺健司, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 75th 2014

Development and Application of a Compact Rotating-sample Magnetometer Using HTS-SQUID

堺健司, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

低温工学 49 ( 7 ) 2014

HTS-SQUID回転型磁化率計の高感度化の研究

渡部裕太, 岡本直大, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2014 2014

直冷式HTS-SQUIDを用いた太陽電池の光応答特性評価システムの開発

田中洸平, 糟谷尚平, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2014 2014

HTS-SQUIDを用いた高精度磁化率計の開発と水溶液中の磁気ナノ粒子への応用

森田洪爾, SAARI Mohd Mawardi, 石原優一, 日下瞬, 塚本有哉, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2014 2014

高温超伝導SQUIDを用いた磁化率計の複合型AC/DC検出ユニットの最適化

SAARI Mohd Mawardi, 森田洪爾, 石原優一, 日下瞬, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 75th 2014

高感度磁気センサの非破壊検査への応用磁気抵抗効果センサを用いた非破壊検査

紀和利彦, 堺健司, 塚田啓二

非破壊検査 63 ( 11 ) 2014

HTS-SQUIDを用いた試料回転式磁化率計の試料形状最適化による高感度計測法の検討

堺健司, 岡本直大, 渡部裕太, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

電子情報通信学会大会講演論文集(CD-ROM) 2014 2014

超薄膜Pt/Tiを用いたブリッジ型水素センサの開発

菅井良祐, 武市修蔵, 牛田祐貴, 井並祥太, 堺健司, 紀和利彦, 塚田啓二

センサ・マイクロマシンと応用システムシンポジウム(CD-ROM) 31st 2014

AC/DC高温超伝導SQUID磁化率計による水溶液中の酸化鉄ナノ粒子の磁気特性計測

SAARI Mohd Mawardi, 塚本有哉, 石原優一, 日下瞬, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 61st 2014

保温材下配管外面欠陥の磁気的検査装置の開発

原拓也, 春日基志, 堺健司, 紀和利彦, 塚田啓二

日本磁気学会学術講演概要集 38th 2014

TMRセンサを用いた裏面欠陥の漏洩磁束探傷検査

志賀啓秀, 塚本有哉, 堺健司, 紀和利彦, 西川卓男, 塚田啓二

日本磁気学会学術講演概要集 38th 2014

三層鋼板スポット溶接の磁気を用いた非破壊検査

原田大地, 堺健司, 紀和利彦, 塚田啓二

非破壊検査 63 ( 9 ) 2014

THz-TDSによるPEフィルム含水量の非破壊検査法

松岡泰正, 紀和利彦, 堺健司, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 75th 2014

磁場を用いた保温材下配管の外面欠陥検出と位置特定の検討

堺健司, 春日基志, 橋本源基, 紀和利彦, 塚田啓二, 河部俊英

表面探傷シンポジウム講演論文集 17th 2014

産業応用に向けたテラヘルツ波ケミカル顕微鏡の開発

紀和利彦, 堺健司, 塚田啓二

農業食料工学会誌 76 ( 3 ) 2014

Optimization of the Detection Technique for a Vibrating-Sample Magnetometer Using High-T-c SQUID

Mohd Mawardi Saari, Kenji Sakai, Toshihiko Kiwa, Keiji Tsukada

IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY 23 ( 3 ) 1600204 2013.6

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

We have developed a compact vibrating-sample magnetometer that uses a high-temperature superconductor superconducting quantum interference device (high-T-c SQUID) and a normal conductive pickup coil. To further increase the sensitivity of the developed system, we consider a technique to detect harmonic components induced at the pickup coil. We optimized the geometry of the pickup coil and sample to maximize the harmonic signals and compared the harmonic signals induced from different shapes of coils using simulation and experimental methods. The simulation and the experimental results agreed well, indicating that the optimized geometry of the pickup coil improves the induced harmonic components. Improvement in sensitivity with reduced mechanical noise can be attained using this detection technique.

DOI： 10.1109/TASC.2012.2227919

Magnetic evaluation of a solar panel using HTS-SQUID

Toshihiko Kiwa, Yohei Fukudome, Shingo Miyazaki, Mohd Mawardi Saari, Kenji Sakai, Keiji Tsukada

Physica C: Superconductivity and its Applications 494 ( 15 ) 195 - 198 2013

Language：English Publisher：ELSEVIER SCIENCE BV

The magnetic evaluation system of a solar panel using HTS-SQUID has been proposed and developed. A normal pick-up coil was applied to detect the tangential magnetic field to the panel surface. Since the detected field could be related to the currents of the solar panels, the electric properties of the solar panels could be evaluated. In this work, the evaluation of the electric properties of the commercial solar panels as well as the electric circuits made by the discrete devices on the circuit board was visualized. © 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physc.2013.04.080

テラヘルツケミカル顕微鏡と応用開拓

紀和利彦

O plus E 35 ( 2 ) 147 - 151 2013

Compact rotating-sample magnetometer for relaxation phenomenon measurement using HTS-SQUID

Kenji Sakai, Mohd Mawardi Saari, Toshihiko Kiwa, Keiji Tsukada

IEEE Transactions on Applied Superconductivity 23 ( 3 ) 1601904 2013

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

A compact magnetometer that uses a high-temperature superconductor superconducting quantum interference device (HTS-SQUID) that can measure relaxation phenomena was developed, and its characteristics were evaluated. For measuring magnetic relaxation, a pick-up coil was designed to be fixed at any position in the circle described by a rotating-sample. The pick-up coil was directly connected to an input coil, which is inductively connected to the HTS-SQUID, and the secondary induced magnetic field from the sample was detected with time delay after magnetization. Using the developed system, magnetic signals with time delay from pure water were detected, and the magnetic signal intensity decreased with increasing time delay. This magnetic signal with time delay was not caused by the sample case and the magnetization due to the leaked magnetic field distribution of the permanent magnet used for sample magnetization. Thus, the developed system could detect magnetic signals during the magnetic relaxation process. © 2012 IEEE.

DOI： 10.1109/TASC.2012.2234324

Magnetic detection of currents in an electrolytic cell using high-T <inf>C</inf> SQUID

Toshihiko Kiwa, Yohei Fukudome, Shingo Miyazaki, Mohd Mawardi Saari, Kenji Sakai, Akira Tsukamoto, Seiji Adachi, Keiichi Tanabe, Akihiko Kandori, Keiji Tsukada

IEEE Transactions on Applied Superconductivity 23 ( 3 ) 1600804 2013

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

A magneto-electrical cyclic voltammetry has been proposed and developed. This measurement method utilized three electrodes: a counter, a working, and a reference electrode, as the conventional voltammetry uses and the magnetic field by the currents were detected. Thus, the current distribution in the electrolyte cells during the voltammetry measurements could be visualized. In this work, the current in the cell was observed during the pulse voltammetry using the high-TC SQUID with the normal pick-up coils. The pick-up coil was aligned parallel to the surface of the cell. Obtained magnetic signals could be related to the current measured by the conventional method. © 2002-2011 IEEE.

DOI： 10.1109/TASC.2012.2228736

Compact Vibrating-Sample Magnetometer using High-T_c SQUID and Sample Shape Dependency

高温超伝導SQUIDを用いたDC/AC複合小型磁化率計の開発

高木竜輝, MOHD Mawardi Saari, 石原優一, 堺健司, 紀和利彦, 塚田啓二

低温工学・超電導学会講演概要集 87th 2013

HTS-SQUIDを用いた磁気緩和測定システムの高精度化

堺健司, 岡本直大, 浜崎大地, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

電子情報通信学会大会講演論文集(CD-ROM) 2013 2013

Optimized Rotating-sample Magnetometer Using HTS-SQUID and its Application to Moisture Content Evaluation

堺健司, 日下瞬, 岡本直大, 浜崎大地, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

電子情報通信学会技術研究報告 113 ( 232(SCE2013 19-34) ) 2013

HTS-SQUIDグラジオメータを用いた太陽電池直流電流計測システムの開発

宮崎真伍, 糟谷尚平, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚本晃, 安達誠司, 田辺圭一, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 74th 2013

高温超伝導SQUIDを用いたDC・AC複合小型磁化率計の開発

石原優一, SAARI Mohd Mawardi, 高木竜輝, 堺健司, 紀和利彦, 塚田啓二

日本磁気学会学術講演概要集 37th 2013

高温超伝導SQUIDを用いた小型磁化率計による水分量測定

日下瞬, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

日本磁気学会学術講演概要集 37th 2013

Development of AC-magnetometer Using HTS-SQUID and Optimization of Measurement System

堺健司, 浜崎大地, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

電子情報通信学会技術研究報告 113 ( 149(SCE2013 10-18) ) 2013

THz波ケミカル顕微鏡による燃料電池の触媒反応解析システムの開発

日下鉄也, 萩原隆文, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 74th 2013

HTS-SQUID磁気計測による太陽電池電気特性評価

宮崎真伍, 福留陽平, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

電子情報通信学会大会講演論文集 2013 2013

HTS-SQUIDを用いたサンプル回転方式小型磁気計測計による磁気緩和測定

浜崎大地, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集 2013 ( 2 ) 2013

HTS-SQUIDを用いた電気磁気化学計測システムの開発(II)

紀和利彦, 福留陽平, 宮崎真伍, 高木竜輝, 堺健司, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 60th 2013

白金メタマテリアル構造の水素応答評価

園拓也, 篠宮光博, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 60th 2013

Highly-sensitive measurement technique of a compact magnetometer using HTS-SQUID and rotating sample

堺健司, 浜崎大地, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

電子情報通信学会技術研究報告 112 ( 408(SCE2012 25-38) ) 2013

漏洩磁束探傷法を用いた鋼板の疲労度検出システムの開発

堺健司, 紀和利彦, 塚田啓二, 井上勝美

表面探傷シンポジウム講演論文集 16th 2013

HTS-SQUIDを用いた試料回転式小型磁化率計のシステム改善による高感度化

堺健司, 浜崎大地, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

電子情報通信学会大会講演論文集 2013 2013

HTS-SQUIDによる試料回転式小型磁化率計を用いた水分量計測

堺健司, 浜崎大地, SAARI Mohd Mawardi, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 60th 2013

高感度計測法を用いた高温超伝導SQUID磁化率計

SAARI Mohd Mawardi, 高木竜輝, 堺健司, 紀和利彦, 塚田啓二

応用物理学会春季学術講演会講演予稿集(CD-ROM) 60th 2013

HTS-SQUIDを用いたサンプル回転型小型磁化率計の開発

岡本直大, 浜崎大地, SAARI M. M., 堺健司, 紀和利彦, 塚田啓二

日本磁気学会学術講演概要集 37th 2013

三層鋼板スポット溶接の磁気を用いた非破壊検査

原田大地, 堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2013 2013

スポット溶接内部構造解析用磁気位相マップの開発

SONG Nannan, 塚本有哉, 志賀啓秀, 原田大地, 堺健司, 紀和利彦, CHENG Weiying, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2013 2013

HTS-SQUID磁気特性評価装置におけるAC磁場検出方法の最適化

石原優一, SAARI Mohd Mawardi, 高木竜輝, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2013 2013

テラヘルツ波ケミカル顕微鏡によるイオン計測システムの開発

大川裕貴, 萩原隆文, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 74th 2013

テラヘルツ波光源と応用テラヘルツ波ケミカル顕微鏡と応用開拓

紀和利彦

O plus E ( 399 ) 2013

テラヘルツ波による生体関連物質化学反応センシング

紀和利彦, 萩原隆文, 大村健, 高橋慎治, 堺健司, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 74th 2013

HTS-SQUID磁気特性評価装置における高調波検波方式の研究

塚本有哉, SAARI Mohd Mawardi, 高木竜輝, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2013 2013

高速スキャン型テラヘルツ分光ユニットの雑音特性

難波勇馬, 園拓也, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2013 2013

テラヘルツ電磁波を用いたSiGe薄膜評価システムの開発

中村彰宏, 大村健, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2013 2013

回転型HTS-SQUID磁化率計の高感度検出法の研究

岡本直大, 浜崎大地, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2013 2013

HTS-SQUIDを用いたサンプル回転方式小型磁化率計の高感度化

浜崎大地, 岡本直大, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 74th 2013

保温材下配管外面欠陥の磁気的検査装置の開発

春日基志, 橋本源基, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 64th 2013

白金薄膜抵抗の構造変化による水素応答評価とブリッジ型水素センサの開発

牛田祐貴, 奥井貴博, 武市修蔵, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 64th 2013

HTS-SQUIDを用いた太陽電池の光応答特性分布解析

糟谷尚平, 宮崎真伍, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2013 2013

高温超伝導SQUIDを用いた磁気特性評価装置によるモルタル水分量測定

日下瞬, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2013 2013

白金薄膜の表面構造による水素応答評価

武市修蔵, 奥井貴博, 牛田祐貴, 堺健司, 紀和利彦, 塚田啓二

センサ・マイクロマシンと応用システムシンポジウム(CD-ROM) 30th 2013

HTS-SQUIDを用いたAC/DC複合小型磁化率計の開発

高木竜輝, 石原優一, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 74th 2013

白金薄膜抵抗を用いたブリッジ回路型水素センサの開発

牛田祐貴, 奥井貴博, 武市修蔵, 堺健司, 紀和利彦, 塚田啓二

センサ・マイクロマシンと応用システムシンポジウム(CD-ROM) 30th 2013

低周波磁場を用いた金属疲労画像化装置

秋山貴俊, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 64th 2013

保温材下配管外面欠陥の磁気的検査装置の開発-その3

橋本源基, 堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2013 2013

テラヘルツ波を用いた生体関連イオン計測手法の開発

大川裕貴, 萩原隆文, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2013 2013

テラヘルツ波ケミカル顕微鏡を用いた寒天ゲル膜の評価

中村彰宏, 大村健, 堺健司, 紀和利彦, 塚田啓二

日本分光学会テラヘルツ分光部会シンポジウム講演要旨集 2013 2013

THz波ケミカル顕微鏡による発電中の燃料電池触媒反応解析

日下鉄也, 萩原隆文, 堺健司, 紀和利彦, 塚田啓二

応用物理・物理系学会中国四国支部合同学術講演会講演予稿集 2013 2013

テラヘルツ波バイオ検査装置の開発と現状

紀和利彦

日本分光学会テラヘルツ分光部会シンポジウム講演要旨集 2013 2013

白金ナノ薄膜の水素応答評価

武市修蔵, 奥井貴博, 牛田祐貴, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 64th 2013

SAARI Mohd Mawardi, TAKAGI Ryuuki, SAKAI Kenji, KIWA Toshihiko, TSUKAMOTO Akira, ADACHI Seiji, TANABE Keiichi, KANDORI Akihiko, TSUKADA Keiji

Technical report of IEICE. SCE 112 ( 138 ) 31 - 36 2012.7

Language：English Publisher：The Institute of Electronics, Information and Communication Engineers

In this study, we have developed a compact vibrating-sample magnetometer that utilizing a normal pickup coil and an SQUID. Optimizations on dependency of sample shape, sample position relative to pickup coil etc. were performed by experiment and simulation results. The present measurement system successfully measured the weak diamagnetism of water and exhibited the sensitivity of 1×10^<-7> emu.

CiNii Article

CiNii Books

Work function shifts of catalytic metals under hydrogen gas visualized by terahertz chemical microscopy. International journal

Toshihiko Kiwa, Takafumi Hagiwara, Mitsuhiro Shinomiya, Kenji Sakai, Keiji Tsukada

Optics express 20 ( 11 ) 11637 - 42 2012.5

Language：English Publisher：OPTICAL SOC AMER

Terahertz chemical microscopy (TCM) was applied to visualize the distribution of the work function shift of catalytic metals under hydrogen gas. TCM measures the chemical potential on the surface of a SiO(2)/Si/sapphire sensing plate without any contact with the plate. By controlling the bias voltage between an electrode on the SiO(2)/ surface and the Si layer, the relationship between the voltage and the THz amplitude from the sensing plate can be obtained. As a demonstration, two types of structures were fabricated on the sensing plate, and the work function shifts due to catalytic reactions were visualized.

DOI： 10.1364/OE.20.011637

Development of a compact moving-sample magnetometer using high-Tc superconducting quantum interference device

Mohd Mawardi Saari, Kenji Sakai, Toshihiko Kiwa, Akira Tsukamoto, Seiji Adachi, Keiichi Tanabe, Akihiko Kandori, Keiji Tsukada

Japanese Journal of Applied Physics 51 ( 4 PART 1 ) 046601 2012.4

Language：English Publisher：IOP PUBLISHING LTD

We developed a compact moving-sample magnetometer that uses a high-temperature superconductor-superconducting quantum interference device (high-T c SQUID) to directly measure the flux coupled to a normal detection coil from a sample's magnetic moment in the presence of an external DC magnetic field. The moving-sample method is employed by inserting the sample between the poles of a DC electromagnet and vibrating the sample along the axis perpendicular to the external field axis using an actuator at a frequency of 2.693 Hz. First, the magnetic field of the sample is transferred by a first-order differential normal Cu coil to a SQUID for detection. Then, the SQUID output is fed to a lock-in amplifier for detection. The critical feature of the system design is the use of high-T c SQUID, which enables the realization of a compact system. The basic characteristics of the developed system are presented, and the current system exhibited a detection limit of 1 x 10 -7 emu. © 2012 The Japan Society of Applied Physics.

DOI： 10.1143/JJAP.51.046601

Electric Characteristics of a Loop in Which Two Junctions between a Catalytic Metal and a Noncatalytic Metal Are under Different Hydrogen Gas Concentrations

Keiji Tsukada, Kenji Sakai, Toshihiko Kiwa

APPLIED PHYSICS EXPRESS 5 ( 3 ) 034102 2012.3

Language：English Publisher：JAPAN SOC APPLIED PHYSICS

To investigate the localized electrochemical properties of an electrode composed of platinum (Pt), a thin-film loop containing two junctions between the catalytic metal Pt and the noncatalytic metal titanium was fabricated. When the loop was open and only one junction was exposed to 10% hydrogen in nitrogen gas, an output voltage change of about 30 nV was generated between these two junctions. The electron density change due to the equilibrium reaction of hydrogen dissociation along the part exposed to hydrogen induced a balance between the diffusion and drift caused by the electric field at both ends of the Pt film. (c) 2012 The Japan Society of Applied Physics

DOI： 10.1143/APEX.5.034102

Changes in work function and electrical resistance of Pt thin films in the presence of hydrogen gas

Keiji Tsukada, Hirotsugu Inoue, Fumiya Katayama, Kenji Sakai, Toshihiko Kiwa

Japanese Journal of Applied Physics 51 ( 1 ) 015701 2012.1

Language：English Publisher：JAPAN SOC APPLIED PHYSICS

The changes in the electrical properties, such as work function and resistance, of Pt thin films in the presence of hydrogen gas were studied. They were simultaneously measured with a flow-through cell at different concentrations of hydrogen gas in atmosphere containing gaseous nitrogen and that containing air. The resistance was measured by a four-terminal sensing method and the relative work function changes were measured using a field effect transistor. In both atmospheres, the resistance decreased as the concentration of hydrogen gas increased. This result was repeatable only in air because of the differences in the dynamic mechanism of increased density of electrical carriers inside the Pt film as a result of diffused H atoms. In the nitrogen atmosphere, the diffused H atoms were not easily released because of the surface barrier. On the other hand, oxygen gas reacted with H atoms at the surface and this reaction accelerated atom release into air. The work function showed repeatable responses in both atmospheres, but the response characteristics were different. The equilibrium reaction between the adsorption and desorption of hydrogen occurred at the surface in the nitrogen atmosphere, whereas the equilibrium reaction of hydrogen and oxygen to form water molecules occurred in air. The changes in work function and resistance in the presence of hydrogen were due to changes in dissociated hydrogen intensity in the bulk, as well as to the surface reactions. © 2012 The Japan Society of Applied Physics.

DOI： 10.1143/JJAP.51.015701

Non-destructive evaluation system using high-Tc SQUID

紀和利彦, 福留陽平, 堺健司, 塚本晃, 安達成司, 田辺圭一, 神鳥昭彦, 塚田啓二

電子情報通信学会技術研究報告 111 ( 418(SCE2011 19-26) ) 11 - 16 2012

Biosensing by a terahertz chemical microscope.

紀和利彦

応用物理 81 ( 4 ) 298 - 303 2012

テラヘルツ波ケミカル顕微鏡による抗原非標識定量計測

高橋慎治, 天満陽, 紀和利彦, 堺健司, 塚田啓二

応用物理学会中国四国支部・日本物理学会中国支部・四国支部・日本物理教育学会中国四国支部支部学術講演会講演予稿集 2012 2012

高温超伝導SQUIDを用いた交流磁気特性計測システムの開発

山口嘉竜, 前田敏志, 浜崎大地, 堺健司, 紀和利彦, 塚本晃, 安達成司, 田辺圭一, 神鳥明彦, 塚田啓二

応用物理学関係連合講演会講演予稿集(CD-ROM) 59th 2012

薄膜抵抗型水素センサの開発

奥井貴博, 片山文哉, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集 2012 ( 3 ) 2012

参照電極が不要なイオンセンサの応答機構解析

山本貴文, 小森達也, 小田和代, 堺健司, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集 2012 ( 3 ) 2012

Characterization of New Structural Sodium Ion Sensor using Electrochemical Impedance Method

小森達也, 山本貴文, 堺健司, 紀和利彦, 塚田啓二

電気学会ケミカルセンサ研究会資料 CHS-12 ( 1-16 ) 2012

異なる白金薄膜構造をもつ抵抗変化式水素センサの応答解析

奥井貴博, 堺健司, 紀和利彦, 塚田啓二

センサ・マイクロマシンと応用システムシンポジウム(CD-ROM) 29th 2012

保温材下配管外面欠陥の磁気的検査装置の開発-その2

橋本源基, 堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2012 2012

HTS-SQUIDを用いた磁気緩和測定用小型磁化率計の開発

堺健司, SAARI Mohd Mawardi, 浜崎大地, 紀和利彦, 円福敬二, 塚田啓二

応用物理学会学術講演会講演予稿集(CD-ROM) 73rd 2012

高温超伝導SQUIDを用いた直流磁化率計の高感度計測法

SAARI Mohd Mawardi, 高木竜輝, 堺健司, 紀和利彦, 塚田啓二

応用物理学会学術講演会講演予稿集(CD-ROM) 73rd 2012

HTS-SQUIDを用いた電気磁気化学計測システムの開発

紀和利彦, 宮崎真伍, 高木竜輝, 堺健司, 塚田啓二

応用物理学会学術講演会講演予稿集(CD-ROM) 73rd 2012

完全個体型イオンセンサの応答解析とマルチイオンセンサの集積化および性能評価

山本貴文, 小森達也, 小田和代, 堺健司, 紀和利彦, 塚田啓二

センサ・マイクロマシンと応用システムシンポジウム(CD-ROM) 29th 2012

レーザー励起THz顕微鏡によるSiGeウェハの非破壊検査

大村健, 紀和利彦, 山下善文, 堺健司, 斗内政吉, 塚田啓二

応用物理学関係連合講演会講演予稿集(CD-ROM) 59th 2012

テラヘルツ波ケミカル顕微鏡によるタンパク質結合検出

紀和利彦

分光研究 61 ( 1 ) 2012

HTS-SQUIDを用いた太陽電池の電気特性分布計測システムの自動化

福留陽平, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚本晃, 安達誠司, 田辺圭一, 神鳥明彦, 塚田啓二

応用物理学関係連合講演会講演予稿集(CD-ROM) 59th 2012

気密THz-TDSユニットの開発

能勢秀俊, 篠宮光博, 門脇信傑, 児島孝則, 小林正樹, 奥野雅史, 紀和利彦

応用物理学関係連合講演会講演予稿集(CD-ROM) 59th 2012

小型ピックアップコイル結合型HTS-SQUIDを用いた太陽電池特性評価システムの開発

紀和利彦, 福留陽平, 宮崎真伍, 高木竜輝, 堺健司, 塚田啓二

低温工学・超電導学会講演概要集 86th 2012

保温材下配管外面欠陥の磁気的検査装置の開発

橋本源基, 堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2012 2012

磁束透過法によるスポット溶接欠陥検査

原田大地, 塚田啓二, 紀和利彦, 堺健司

日本非破壊検査協会講演大会講演概要集 2012 2012

高温超伝導SQUIDを用いた振動型小型磁化率計の開発

高木竜輝, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理学会中国四国支部・日本物理学会中国支部・四国支部・日本物理教育学会中国四国支部支部学術講演会講演予稿集 2012 2012

HTS-SQUIDを用いたサンプル回転型直流磁化率計の開発

浜崎大地, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理学会中国四国支部・日本物理学会中国支部・四国支部・日本物理教育学会中国四国支部支部学術講演会講演予稿集 2012 2012

ECTを用いたスポット溶接欠陥の内部構造解析

原田大地, 堺健司, 紀和利彦, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2012 2012

テラヘルツ波ケミカル顕微鏡によるイオン反応の可視化

萩原隆文, 篠宮光博, 紀和利彦, 堺健司, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 63rd 2012

HTS-SQUID磁気計測による太陽電池電気特性評価

宮崎真伍, 福留陽平, SAARI Mohd Mawardi, 堺健司, 紀和利彦, 塚田啓二

応用物理学会中国四国支部・日本物理学会中国支部・四国支部・日本物理教育学会中国四国支部支部学術講演会講演予稿集 2012 2012

Evaluation system for catalytic reactions using terahertz chemical microscope

萩原隆文, 篠宮光博, 紀和利彦, 堺健司, 塚田啓二

電気学会ケミカルセンサ研究会資料 CHS-12 ( 1-16 ) 2012

Mapping system of Chemical Reactions using Terahertz Chemical Microscope

紀和利彦, 高橋慎司, 堺健司, 塚田啓二

電気学会ケミカルセンサ研究会資料 CHS-12 ( 1-16 ) 2012

Differential conductivity mapping of solar panels using a high-T <inf>C</inf> superconductor SQUID

T. Kiwa, S. Maeda, K. Miyake, N. Kataoka, A. Tsukamoto, S. Adachi, K. Tanabe, A. Kandori, K. Tsukada

Physica C: Superconductivity and its Applications 471 ( 21-22 ) 1238 - 1241 2011.11

Language：English Publisher：ELSEVIER SCIENCE BV

To visualise the distribution of the electric property of solar cells, we developed a differential conductivity mapping system using high-TC (HTS-) superconductor SQUID with a normal conducting pick-up coil. The bias ac voltage with an offset voltage was applied to a solar panel made from amorphous silicon, and the normal component of the generated magnetic field was lock-in-detected. Thus the measured signal was converted to dB/dV properties, which are inverse-proportional to the differential resistivity, as the function of the offset voltage. By scanning the pick-up coil across the panel surface, we obtained the distribution of dB/dV properties across the solar panel was obtained by scanning the pick-up coil across the panel surface. The distribution of dB/dV on the panel differed between when the light source was on and when it was off. This result suggests that the proposed system is a potential tool for diagnosing the electric properties of solar cells. © 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physc.2011.05.168

A magnetic flux leakage method using a magnetoresistive sensor for nondestructive evaluation of spot welds

Keiji Tsukada, Mitsuteru Yoshioka, Toshihiko Kiwa, Yoshinobu Hirano

NDT and E International 44 ( 1 ) 101 - 105 2011.1

Language：English Publisher：ELSEVIER SCI LTD

Spot welding is widely used for joining metal plates. However, a highly reliable monitoring method is needed to weld a robust structure. For this purpose, we developed a magnetic flux leakage (MFL) system using a magnetoresistive (MR) sensor for nondestructive spot-weld inspection. The magnetic flux is induced between two joined plates, and the magnetic flux leakage with a tangential component parallel to the plate surface is measured. A magnetic image at the spot-welding part is obtained by two-dimensional scanning. The connected diameter of the nugget and the maximum shear load are measured after the magnetic measurement to investigate their interrelationship. The results show that the nondestructive magnetic flux leakage test shows a good correlation with the destructive shear test. © 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ndteint.2010.09.012

HTS-SQUIDを用いた交流磁化率計の開発

前田敏志, 山口嘉竜, 堺健司, 紀和利彦, 塚田啓二, 塚本晃, 安達成司, 田辺圭一, 神鳥明彦

低温工学・超電導学会講演概要集 84th 2011

高温超伝導SQUIDを用いた太陽電池の電気特性分布計測

福留陽平, 前田敏志, 紀和利彦, 堺健司, 塚本晃, 安達誠司, 田辺圭一, 神鳥明彦, 塚田啓二

応用物理学会中国四国支部・日本物理学会中国支部・四国支部・日本物理教育学会中国四国支部支部学術講演会講演予稿集 2011 2011

HTS-SQUIDを用いたヘルムホルツ型交流磁化率計の開発

山口嘉竜, 前田敏志, 堺健司, 紀和利彦, 塚本晃, 安達成司, 田辺圭一, 神鳥明彦, 塚田啓二

応用物理学会中国四国支部・日本物理学会中国支部・四国支部・日本物理教育学会中国四国支部支部学術講演会講演予稿集 2011 2011

交流インピーダンス法を用いた新型イオンセンサの特性評価

小森達也, 小田和代, 堺健司, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 62nd 2011

透過磁場検出によるスポット溶接検査法の開発

澤井勇人, 三宅康介, 堺健司, 紀和利彦, 塚田啓二, 平野佳伸

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 62nd 2011

低周波磁場を用いたスポット溶接の非破壊検査

堺健司, 三宅康介, 紀和利彦, 平野佳伸, 松元光明, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2011 2011

テラヘルツ波ケミカル顕微鏡とバイオセンシング

紀和利彦

日本分光学会テラヘルツ分光部会シンポジウム講演要旨集 2011 2011

テラヘルツ波放射制御デバイス磁気特性評価

篠宮光博, 岡田啓太, 堺健司, 紀和利彦, 塚田啓二

応用物理学会中国四国支部・日本物理学会中国支部・四国支部・日本物理教育学会中国四国支部支部学術講演会講演予稿集 2011 2011

テラヘルツ波ケミカル顕微鏡を用いた層流イメージング

橋本陽平, 近藤洋輔, 紀和利彦, 塚田啓二

応用物理学関係連合講演会講演予稿集(CD-ROM) 58th 2011

ダブルパルス検出法によるテラヘルツ波ケミカル顕微鏡の高感度計測

天満陽, 近藤洋輔, 紀和利彦, 門脇信傑, 小林正樹, 塚田啓二

応用物理学関係連合講演会講演予稿集(CD-ROM) 58th 2011

テラヘルツを用いたバイオセンシング

紀和利彦, 天満陽, 橋本陽平, 堺健司, 塚田啓二

日本分光学会赤外ラマン分光部会シンポジウム 6th 2011

HTS-SQUIDを用いた試料回転式小型磁化率計の開発

堺建司, MOHD Mawardi, 紀和利彦, 塚田啓二, 塚本晃, 安達成司, 田辺圭一, 神鳥明彦

低温工学・超電導学会講演概要集 85th 2011

High-T_CSQUIDを用いた太陽電池パネル非破壊検査

紀和利彦, 前田敏志, 三宅康介, 片岡伸夫, 堺健司, 塚本晃, 安達成司, 田辺圭一, 神鳥明彦, 塚田啓二

応用物理学関係連合講演会講演予稿集(CD-ROM) 58th 2011

HTS-SQUIDを用いた小型磁化率計の開発

堺健司, MOHAMADO Mawarudei, 紀和利彦, 塚本晃, 安達成司, 田辺圭一, 神鳥明彦, 塚田啓二

応用物理学関係連合講演会講演予稿集(CD-ROM) 58th 2011

Development of All-solid-state Multi Ion Sensor without a Reference Electrode

小田和代, 小森達也, 堺健司, 紀和利彦, 塚田啓二

電気学会ケミカルセンサ研究会資料 CHS-11 ( 1-24 ) 2011

Development of thin film resistance type Hydrogen sensor

片山文哉, 堺健司, 紀和利彦, 塚田啓二

電気学会マイクロマシン・センサシステム研究会資料 MSS-11 ( 1-7.9-12.14-21 ) 2011

漏洩磁束探傷検査法を用いたスポット溶接欠陥検査用画像化装置の開発

三宅康介, 吉岡光輝, 紀和利彦, 塚田啓二, 平野佳伸, 松元光明

電気学会全国大会講演論文集 2011 ( 2 ) 2011

High-T_cSQUIDを用いた太陽電池パネル接合容量分布計測

紀和利彦, 福留陽平, 前田敏志, 堺健司, 塚本晃, 安達成司, 田辺圭一, 神鳥明彦, 塚田啓二

応用物理学会学術講演会講演予稿集(CD-ROM) 72nd 2011

高温超電導SQUIDを用いた小型磁化率計の開発

MAWARDI Mohd, 前田敏志, 堺健司, 紀和利彦, 塚本晃, 安達成司, 田辺圭一, 神鳥明彦, 塚田啓二

応用物理学会学術講演会講演予稿集(CD-ROM) 72nd 2011

ダブルパルス検出法によるテラヘルツ波ケミカル顕微鏡のノイズキャンセル

天満陽, 紀和利彦, 門脇信傑, 小林正樹, 堺健司, 塚田啓二

応用物理学会学術講演会講演予稿集(CD-ROM) 72nd 2011

保温断熱配管の磁気的非破壊検査方法の開発

土井貴範, 三宅康介, 紀和利彦, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2011 2011

テラヘルツ波面制御素子の放射パターン制御評価

篠宮光博, 岡田啓太, 堺健司, 紀和利彦, 塚田啓二

日本分光学会テラヘルツ分光部会シンポジウム講演要旨集 2011 2011

High-T_cSQUIDを用いた太陽電池パネル電気特性分布計測

紀和利彦, 前田敏志, 三宅康介, 堺健司, 塚田啓二, 塚本晃, 安達成司, 田辺圭一, 神鳥明彦

低温工学・超電導学会講演概要集 84th 2011

テラヘルツ電磁波技術研究会

川瀬晃道, 紀和利彦

應用物理 79 ( 9 ) 845 - 845 2010.9

Terahertz electronics

79 ( 8 ) 697 - 699 2010.8

Terahertz chemical microscope for label-free detection of protein complex

Toshihiko Kiwa, Yousuke Kondo, Yuji Minami, Iwao Kawayama, Masayoshi Tonouchi, Keiji Tsukada

Applied Physics Letters 96 ( 21 ) 2010.5

Language：English Publisher：AMER INST PHYSICS

A terahertz (THz) chemical microscope (TCM) has been proposed and developed for label-free analysis of the interactions of proteins, including immune reactions. A SiO2/Si/sapphire plate was fabricated and emitted THz pulses from the sapphire side using a femtosecond laser. The amplitude of a THz pulse depends on the chemical potential of the SiO2 surface. As an initial demonstration, a biotin-avidin complex was analyzed using TCM. Results indicate that biotin concentrations of up to 10-12 mol/l could be detected, suggesting that a high sensitivity immunoassay system can be realized using this method. The distribution of the THz peak amplitude was measured, reflecting the distribution of the biotin-avidin complex on the plate. © 2010 American Institute of Physics.

DOI： 10.1063/1.3441408

Dual-Gate field-effect transistor hydrogen gas sensor with thermal compensation

Keiji Tsukada, Masatoshi Kariya, Tomiharu Yamaguchi, Toshihiko Kiwa, Hironobu Yamada, Tsuneyoshi Maehara, Tadayoshi Yamamoto, Shinsuke Kunitsugu

Japanese Journal of Applied Physics 49 ( 2 Part 1 ) 2010.2

Language：English Publisher：IOP PUBLISHING LTD

We developed a dual-gate field-effect transistor (FET) hydrogen gas sensor for application to hydrogen vehicles. The dual-gate FET hydrogen sensor was integrated with a Pt-gate FET to detect hydrogen and a Ti-gate FET as the reference sensor in the same Si chip. The Ti-FET had the same structure as the Pt-FET except for the gate metal. The Pt-FET showed a good response to hydrogen gas above 10ppm in air, while the Ti-FET did not show any response to hydrogen gas. The differential output voltage between the Pt-FET and the Ti-FET was stable in the temperature range from room temperature to 80 °C because of the same temperature dependence of the current-voltage (I-V) characteristics. In addition, the temperature of the integrated hydrogen sensor was controlled by an integrated system consisting of a heater and a thermometer at any given temperature under severe weather conditions. © 2010 The Japan Society of Applied Physics.

DOI： 10.1143/JJAP.49.024206

Evaluation of the sensitivity of hydrogen sensors covered with polytetrafluoroethylene as a protective membrane for humidity

Koji Fujii, Hirotsugu Inoue, Tomiharu Yamaguchi, Toshihiko Kiwa, Keiji Tsukada

IEEJ Transactions on Sensors and Micromachines 130 ( 8 ) 401 - 406 2010

Language：English

Environmental factors such as dust adsorption effects and humidity generally result in drifts of the sensor output signal and lead tomalfunctions of the sensor and/or reduction in sensitivity. So a sensor package is necessary to protect hydrogen sensors in order to operate the sensors in an actual use environment. In this study, a Pt-FET hydrogen sensor covered with a polytetrafluoroethylene (PTFE) porous membrane was developed. The PTFE porous membrane with different pore sizes of 5 μm, 20 μm A and 30 μm was applied and the effects of humidity on sensor sensitivity were evaluated. The results indicate the effects of humidity on the sensitivity were reduced in the relative humidity range between 20% and 80% for the sensor with the 5-μm porous membrane. © 2010 The Institute of Electrical Engineers of Japan.

DOI： 10.1541/ieejsmas.130.401

Development and evaluation of a Pt/Ti-FET-type hydrogen sensor

Masatoshi Kariya, Kouhei Mizuhara, Tomiharu Yamaguchi, Toshihiko Kiwa, Shinsuke Kunitsugu, Keiji Tsukada

IEEJ Transactions on Sensors and Micromachines 130 ( 8 ) 407 - 411 2010

Language：English

A novel gate-structure FET-type hydrogen sensor (Pt/Ti-FET) thathas an adhesion layer (Ti) between the catalytic metal (Pt) and the gate insulator was fabricated. The dependence of the response characteristics of the sensitivity and selectivity on the Ti thickness was investigated. The sensitivity showed dependence on Ti thickness, and higher sensitivity was obtained with a decrement in Ti thickness. In addition, the Pt/Ti-FET showed good selectivity against other gases (02, C2H6) compared with the Pt-FET. After annealing at 260°C for 30 min under 5 Pa in a vacuum, the Pt/Ti-FET showed different response characteristics from an as-depositedPt/Ti- FET. The annealed Pt/Ti-FETs with a thin Ti adhesion layer (below 10 nm) showed improved hydrogen sensitivity. In particular, the Ti5-nm sample of the Pt/Ti-FET sensor showed a higher hydrogen responsewhen exposed to 0.8% hydrogen gas (526.2 mV) compared to that of the Pt-FET sensor (415.7 mV). However, improvement in hydrogen sensitivity was not obtained in thick Ti samples. Additionally the annealed Pt/Ti-FET showed better selectivity against 0 2 than as-deposited Pt/Ti-FET. © 2010 The Institute of Electrical Engineers of Japan.

DOI： 10.1541/ieejsmas.130.407

セキュアライフを支えるテラヘルツ波技術テラヘルツ波ケミカル顕微鏡による非標識バイオセンシング

紀和利彦

Bio Industry 27 ( 10 ) 14 - 19 2010

Detectionofback-sidepitonaferrousplatebymagneticfluxleakagemethod with analyzingmagneticfieldvector

Keiji Tsukada, Mitsuteru Yoshioka, Yoshihiko Kawasaki, Toshihiko Kiwa

NDT & E International 43 ( 4 ) 323 - 328 2010

テラヘルツ波センシングプレート封入型検査セルの開発

紀和利彦

村田学術振興財団年報 ( 24 ) 2010

Hydrogen Response Characteristic of Platinum Thin Film

水原宏平, 片山文哉, 紀和利彦, 塚田啓二

電気学会ケミカルセンサ研究会資料 CHS-10 ( 1-6.8-14 ) 2010

HTS-SQUIDを用いた磁気特性計測システムの開発

前田敏志, 片岡伸夫, 紀和利彦, 塚本晃, 安達成司, 田辺圭一, 神鳥明彦, 塚田啓二

応用物理学会学術講演会講演予稿集(CD-ROM) 71st 2010

HTS-SQUIDを用いた太陽電池の微分抵抗特性分布測定

紀和利彦, 前田敏志, 三宅康介, 片岡伸夫, 塚本晃, 安達成司, 田辺圭一, 塚田啓二

応用物理学会学術講演会講演予稿集(CD-ROM) 71st 2010

低周波磁場を用いた金属疲労検査法の開発

三宅康介, 吉岡光輝, 紀和利彦, 櫻本昌宏, 井上勝美, 塚田啓二

日本磁気学会学術講演概要集 34th 2010

スポット溶接評価用漏洩磁束探傷検査法

吉岡光輝, 三宅康介, 紀和利彦, 平野佳伸, 松本光明, 塚田啓二

日本非破壊検査協会講演大会講演概要集 2010 2010

テラヘルツ波ケミカル顕微鏡によるpH分布評価応用

近藤洋輔, 橋本陽平, 天満陽, 紀和利彦, 塚田啓二

応用物理学会中国四国支部・日本物理学会中国支部・四国支部・日本物理教育学会中国四国支部支部学術講演会講演予稿集 2010 2010

テラヘルツ波ケミカル顕微鏡のμ-TAS測定

橋本陽平, 近藤洋輔, 紀和利彦, 川山巌, 斗内政吉, 塚田啓二

応用物理学会学術講演会講演予稿集(CD-ROM) 71st 2010

テラヘルツ波面制御デバイスの開発と評価

別府慶治, 杉本武史, 紀和利彦, 塚田啓二

応用物理学関係連合講演会講演予稿集(CD-ROM) 57th 2010

テラヘルツ波面制御デバイスの開発

別府慶治, 紀和利彦, 塚田啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 61st 2010

触媒金属ゲートFETにおける応答メカニズムの解析

井上大嗣, 片山文哉, 水原宏平, 紀和利彦, 塚田啓二

センサ・マイクロマシンと応用システムシンポジウム(CD-ROM) 27th 2010

FET型センサを用いた新型酸素センサの開発

切明大輔, 片山文哉, 紀和利彦, 塚田啓二

センサ・マイクロマシンと応用システムシンポジウム(CD-ROM) 27th 2010

保温断熱配管の磁気的非破壊検査方法の開発

三宅康介, 吉岡光輝, 土井貴範, 紀和利彦, 塚田啓二, 河部俊英, 藤田理絵, 花口正典

日本非破壊検査協会講演大会講演概要集 2010 2010

テラヘルツ波ケミカル顕微鏡を用いた植物断面のpH分布イメージング

近藤洋輔, 南祐治, 紀和利彦, 川山巌, 斗内政吉, 塚田啓二

応用物理学関係連合講演会講演予稿集(CD-ROM) 57th 2010

テラヘルツ波ケミカル顕微鏡の高感度化に向けたダブルパルス検出法の開発

天満陽, 近藤洋輔, 紀和利彦, 塚田啓二

応用物理学会中国四国支部・日本物理学会中国支部・四国支部・日本物理教育学会中国四国支部支部学術講演会講演予稿集 2010 2010

PROTON-PUMPING GATE STRUCTURE FOR A FIELD-EFFECT TRANSISTOR TYPE HYDROGEN SENSOR

山口富治, 假谷正敏, 紀和利彦, 塚田啓二

Chemical Sensors 77th ( Supplement A ) 2010

DEVELOPMENT OF A NEW TYPE MICRO ION SENSOR WITHOUT A REFERENCE ELECTRODE

井上豊崇, 小田和代, 山田博信, 紀和利彦, 塚田啓二

Chemical Sensors 2010 ( 3 ) 2010

溶接部内部欠陥検出用磁気センサアレイプローブの開発

三宅康介, 萬治寧大, 紀和利彦, 塚田啓二, 櫻本昌宏, 井上勝美

電気学会全国大会講演論文集 2010 ( 2 ) 2010

PROTON-PUMPING GATE STRUCTURE FOR A FIELD-EFFECT TRANSISTOR TYPE HYDROGEN SENSOR

山口富治, 假谷正敏, 紀和利彦, 塚田啓二

Chemical Sensors 26 ( Supplement A ) 2010

A novel ion sensor without a reference electrode

Keiji Tsukada, Fumiyuki Kobayashi, Toyotaka Inoue, Toshihiko Kiwa

Sensor Letters 7 ( 6 ) 1163 - 1166 2009.12

Language：English Publisher：AMER SCIENTIFIC PUBLISHERS

We developed an ion sensor with a novel structure that does not require a reference electrode. The structure consists of a double electrode comprising an outer electrode with a hole and an inner electrode, a polymeric ion-selective membrane, and the sensor body. The ion sensitivity of a potassium ion sensor, where the hole of the outer electrode was the same size as the inner electrode, was 55 mV/decade. The sensor exhibited increased sensitivity according to the increment of the hole size. The sensitivity was also dependent on the thickness of the outer membrane covering the outer electrode. These phenomena were examined using a membrane potential gradient simulation. Copyright © 2009 American Scientific Publishers All rights reserved Printed in the United States of America.

DOI： 10.1166/sl.2009.1240

Magnetic thickness gauge using a Fourier transformed eddy current technique

Toshihiko Kiwa, Takayuki Hayashi, Yoshihiko Kawasaki, Hironobu Yamada, Keiji Tsukada

NDT and E International 42 ( 7 ) 606 - 609 2009.10

Language：English Publisher：ELSEVIER SCI LTD

A Fourier-transformed eddy current (FTEC) technique has been proposed and developed. This technique employs Fourier transformation analysis to analyze pulsed eddy current signals measured by magnetoresistive sensors. The advantage of this technique is that the intrinsic response, Gamp (f), of a sample material can be extracted without it being affected by the characteristics of the measurement systems. Aluminum plates with an area of 100 mm × 100 mm and various thicknesses were used as test samples. We examined the relationship between the thickness of the sample and the frequency, when Gamp (f)'s reached 90% of the maximum magnitude. The results indicate that FTEC can be used for non-contact measurements of conductive materials. We also evaluated lift-off effects for Gamp (f) for 1- and 5-mm-thick samples. The deviations of the frequencies for the 90% response were 453.386 ± 14.37 and 99.789 ± 4.13 Hz for the 1- and 5-mm-thick samples, respectively. This result indicates that the lift-off effect was reduced by the FTEC analysis. © 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ndteint.2009.04.003

Non-contact thickness gauge for conductive aterials using HTS SQUID system

Toshihiko Kiwa, Hideaki Tahara, Etsuro Miyake, Hironobu Yamada, Keiji Tsukada

IEEE Transactions on Applied Superconductivity 19 ( 3 ) 801 - 803 2009.6

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Eddy current testing using high-Tc superconductive (HTS) superconducting quantum interference devices (SQUID), was developed to realize non-contact thickness gauge measurement of conductive materials, due to their high-sensitivity to magnetic fields generated by eddy currents. A HTS SQUID pulsed eddy current system with Fourier transform analysis is proposed and demonstrated. Aluminum plates (10 × 10 mm) with thicknesses in the range of 1 to 10 mm were used as test samples. The intrinsic responses Ga(f) of the samples were successfully extracted. The slopes of these responses were estimated by linear fitting, and plotted as a function of sample thickness. The Ga(f) slopes decrease with increasing thickness of the test samples. The analysed data suggests that this system can be used as a non-contact thickness gauge for conductive materials. © 2009 IEEE.

DOI： 10.1109/TASC.2009.2019196

Magnetic image detection of the stainless-steel welding part inside a multi-layered tube structure

Takayuki Hayashi, Yoshihiko Kawasaki, Hironobu Yamada, Toshihiko Kiwa, Masaji Tamazumi, Keiji Tsukada

NDT and E International 42 ( 4 ) 308 - 315 2009.6

Language：English Publisher：ELSEVIER SCI LTD

The stainless-steel welding part inside a multi-layered tube was successfully detected using low-frequency magnetic imaging. The magnetic images were obtained by the developed measurement system, consisting of an exposure coil, magnetoresistive (MR) sensor, lock-in amplifier, x-y stage, revolving stage with a horizontal level stage and personal computer. To expose the magnetic field to a wide area of the stainless-steel sample, the radius of the exposure coil was made comparable to the sample size. The MR sensor measured the vector components of the magnetic field generated from the sample within the range of low frequencies between 50 Hz and 1 kHz. A cylindrical stainless-steel sample was fabricated as a tube by rolling a stainless-steel sheet and welding each edge using arc welding with argon as shielding gas. The normal components (Bz) and tangential components (Bx and By) to the sample surface were measured by scanning the MR sensor on the sample surface and the magnetic characteristics of each of the component images were documented. As a result, the difference in permeability between the weld area and the base material was successfully visualized as magnetic images. © 2008 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ndteint.2008.12.006

Highly sensitive measurement of moisture content using HTS-SQUID

Keiji Tsukada, Toshihiko Kiwa, Hideaki Tahara, Etsuro Miyake, Hironobu Yamada, Akira Tsukamoto, Akihiko Kandori

IEEE Transactions on Applied Superconductivity 19 ( 3 ) 878 - 881 2009.6

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

We developed a highly sensitive magnetic system for measuring moisture content using an HTS-SQUID sensor. The system consists mainly of an exposure coil, a Dewar flask containing HTS-SQUID immersed in liquid nitrogen, a cancellation coil, a lock-in amplifier, magnetically shielded box, and FLL circuit. The cancellation coil was used to eliminate the applied magnetic field at the sensor position, and then a cancellation ratio of more than -40 dB was obtained. By the high performance, the subject can be exposed to a powerful magnetic field strength in the order of μT, and a weak magnetic signal of less than tens of pT from the subject can be detected. Using a magnetic vector analysis technique, more precise measurement of moisture content is realized. © 2009 IEEE.

DOI： 10.1109/TASC.2009.2019659

Temperature control and packaging optimization of the integrated hydrogen sensor

Kousuke Tsubota, Toshihiko Kiwa, Hironobu Yamada, Tomiharu Yamaguchi, Yohei Kondo, Hirofumi Imajo, Tsutomu Hondo, Tunetoshi Maehara, Tadayoshi Yamamoto, Keiji Tsukada

IEEJ Transactions on Sensors and Micromachines 129 ( 9 ) 2 - 282 2009

Language：English

An integrated sensor chip combining a heater for temperature control and a diode for temperature monitoring was fabricated and its characteristics evaluated. Furthermore, a new packaging structure with a gas permeable film and sensor chip attached to the glass to improve the heat efficiency were developed. Using this packaging structure, the optimum working conditions and protection for the sensor chip were realized. The features of the diode were suffïcient to verify the sensor temperature. In terms of the value of heat efficiency per power consumption, we succeeded in advancing its values by about 15% compared to the glassless type. Furthermore, the time response curves for the sensor temperature and power consumption of the heater were measured. The thermal control System consists of a heater and the diode was successfully utilized to maintain the intended temperature. The heat efficiency was improved by attaching a glass and this System was found to be useful for the PPG-FET type hydrogen sensor. ©; 2009 The Institute of Electrical Engineers of Japan.

DOI： 10.1541/ieejsmas.129.278

Hydrogen selectivity of a proton-pumping gate FET hydrogen sensor in an AC modulation mode

Tomiharu Yamaguchi, Masanori Takisawa, Toshihiko Kiwa, Hironobu Yamada, Keiji Tsukada

IEEJ Transactions on Sensors and Micromachines 129 ( 4 ) 110 - 114 2009

Language：English

The response characteristics of a proton pumping gate FET (PPG-FET) with a triple layer gate structure (Pd/proton conducting polymer/Pt) to various gases were investigated. Two kinds of hydrogen response signals (DC and AC) were obtained from the PPG-FET when the AC bias voltage was applied between the gate electrodes of the PPG-FET. The DC signals showed high hydrogen sensitivities and the sensitivities were about -30 mV/decade. Additionally, the AC signal decreased by 10 mV with increase in the hydrogen concentration from 100 ppm to 10%. Whereas the DC signals decreased slightly with increasing oxygen concentration, the oxygen response was much smaller than the DC hydrogen sensitivities. In contrast, the AC signal hardly responded to oxygen. This is because a proton conducting polymer layer prevents the movement of oxygen ions. Additionally, the proton pumping gate FET showed good selectivity against other gases (methane, ethane, ammonia, and methanol). These results clarify the high hydrogen sensitivity of the PPG-FET in an AC modulation mode. © 2009 The Institute of Electrical Engineers of Japan.

DOI： 10.1541/ieejsmas.129.110

Measurement of pH in fluidic chip using a terahertz chemical microscope

Toshihiko Kiwa, Shohei Oka, Yuji Minami, Iwao Kawayama, Masayoshi Tonouchi, Keiji Tsukada

IEEJ Transactions on Sensors and Micromachines 129 ( 7 ) 221 - 224 2009

Language：English

A terahertz chemical microscope (TCM) has been developed to visualize the chemical concentration of solutions in fluidic chips. Chemical potential-terahertz transducers were newly developed and applied to the bottom surfaces of the flow channels. When femtosecond laser pulses hit the transducers, terahertz waves are radiated from them. Since the amplitude of terahertz waves can be related to the chemical potential on the surface of the device, the distribution of chemical reactions on the surface can be visualized by scanning the laser on the device. Here, we report the demonstration of mapping of pH values using TCM with a spatial resolution of less than 1 mm. The pH distribution of the flow channels filled with 0.01 M NaOH and HC1 was successfully visualized. In addition, the neutralization process was monitored. © 2009 The Institute of Electrical Engineers of Japan.

DOI： 10.1541/ieejsmas.129.221

テラヘルツ波ケミカル顕微鏡を用いたアビジン-ビオチン結合の検出

近藤洋輔, 南祐治, 紀和利彦, 川山巌, 斗内政吉, 塚田啓二

応用物理学会学術講演会講演予稿集 70th ( 3 ) 2009

プロトンポンピングゲートFETをベースとした集積化水素ガスセンサの開発

山口富治, 坪田公輔, 山田博信, 紀和利彦, 塚田啓二, 近藤洋平, 今城啓文, 本藤勉, 前原経利, 山本忠義

電気学会全国大会講演論文集 2009 ( 3 ) 2009

低周波磁気ベクトル解析による鉄鋼板厚みの非破壊検出方法

林孝之, 林孝之, 川崎喜彦, 山田博信, 紀和利彦, 井上勝美, 塚田啓二

日本非破壊検査協会大会講演概要集 2009 2009

印加磁場直交配置型HTS-SQUID非破壊検査装置の開発

紀和利彦, 三宅悦朗, 山田博信, 塚本晃, 塚田敬二

応用物理学会学術講演会講演予稿集 70th ( 1 ) 2009

低周波磁場を用いた漏洩磁束探傷試験

吉岡光輝, 川崎喜彦, 紀和利彦, 塚出啓二

電気・情報関連学会中国支部連合大会講演論文集(CD-ROM) 60th 2009

高温超伝導SQUIDを用いたフーリエ型パルス渦流探傷法による金属板の欠陥検出

三宅悦朗, 田原秀哲, 山田博信, 紀和利彦, 塚田啓二

応用物理学関係連合講演会講演予稿集 56th ( 1 ) 2009

Pt/Ti二層ゲートFET型水素センサの空気雰囲気での水素応答特性

假谷正敏, 山口富治, 紀和利彦, 山田博信, 塚田啓二, 國次真輔

電気学会全国大会講演論文集 2009 ( 3 ) 2009

ガス透過膜の水素センサへの適用

藤井浩二, 山口富治, 紀和利彦, 山田博信, 塚田啓二

電気学会全国大会講演論文集 2009 ( 3 ) 2009

テラヘルツ波ケミカル顕微鏡を用いた固定化酵素反応イメージング

南祐治, 岡昇平, 紀和利彦, 川山巌, 斗内政吉, 塚田啓二

応用物理学関係連合講演会講演予稿集 56th ( 3 ) 2009

HTS-SQUIDを用いた直交磁場印加型非破壊検査システムの開発

三宅悦朗, 紀和利彦, 塚田啓二, 塚本晃

低温工学・超電導学会講演概要集 81st 2009

DEVELOPMENT OF A NEW TYPE MICRO ION SENSOR WITHOUT A REFERENCE ELECTRODE

井上豊崇, 小田和代, 山田博信, 紀和利彦, 塚田啓二

Chemical Sensors 25 ( Supplement B ) 2009

フーリエ変換過流探傷法による鉄鋼板厚の非破壊検出

林孝之, 林孝之, 川崎喜彦, 吉岡光輝, 山田博信, 紀和利彦, 井上勝美, 塚田啓二

日本磁気学会学術講演概要集 33rd 2009

磁気を用いたモルタルの水分含有量の測定方法

片岡伸夫, 増田康孝, 山田博信, 紀和利彦, 尾藤良孝, 塚田啓二

日本磁気学会学術講演概要集 33rd 2009

Analysis of response mechanism of a proton-pumping gate FET hydrogen gas sensor in air

T. Yamaguchi, M. Takisawa, T. Kiwa, H. Yamada, K. Tsukada

Sensors and Actuators, B: Chemical 133 ( 2 ) 538 - 542 2008.8

Language：English Publisher：ELSEVIER SCIENCE SA

Two different types of hydrogen response signals (DC and AC) of a proton-pumping gate FET with triple layer gate structure (Pd/proton conducting polymer/Pt) were obtained. The proton-pumping gate FET showed good selectivity against other gases (CH4, C2H6, NH3, and O2). For practical use, the hydrogen response characteristics of the proton-pumping gate FET were investigated in air (a gaseous mixture of oxygen and nitrogen). The proton-pumping gate FET showed different hydrogen response characteristics in nitrogen as well as in air, despite the lack of oxygen interference independently. To clarify the response mechanism of the proton-pumping gate FET, a hydrogen response measurement was performed, using a gas flow system and electrochemical impedance spectroscopy. Consequently, the difference in response between nitrogen and air was found to be due to the hydrogen dissociation reaction and the interference with the proton transfer caused by the adsorbed oxygen on the upper Pd gate electrode. © 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2008.03.021

Chemical sensing plate with a laser-terahertz monitoring system. International journal

Toshihiko Kiwa, Junichi Kondo, Shohei Oka, Iwao Kawayama, Hironobu Yamada, Masayoshi Tonouchi, Keiji Tsukada

Applied optics 47 ( 18 ) 3324 - 7 2008.6

Language：English Publisher：OPTICAL SOC AMER

A new type of laser-terahertz emission system for noncontact investigations of chemical solutions has been developed. The system monitors terahertz emission from a sensing plate, which consists of silicon oxide and silicon thin film layers on a sapphire substrate. Sensing of chemical solutions with pH values between 1.68 and 10.01 was demonstrated. The amplitude of the terahertz emission from the sensing plate increased with increasing pH value. This change in the amplitude was caused by a change in the depletion layers of the silicon thin film when protons were adsorbed on the surface of the sensing plate. This study demonstrates that full noncontact monitoring of chemical solutions is possible using the laser-terahertz emission system.

DOI： 10.1364/AO.47.003324

Magnetic measurement of the moisture content in soil: Diamagnetic measurement with the presence of ferromagnetic material

Keiji Tsukada, Yasutaka Masuda, Yudai Ishihara, Toshihiko Kiwa

Applied Physics Express 1 ( 6 ) 0670081 - 0670083 2008.6

Language：English Publisher：JAPAN SOC APPLIED PHYSICS

To measure the moisture content of soil, we developed a method that measures the magnetic field generated when the primary magnetic field Is exposed. Soil contains two different types of materials: water as a diamagnetic material and Iron sand as a ferromagnetic material. Water shows a constant phase shift from the primary magnetic field as well as a frequency dependence of the magnetic field strength, and iron sand showed the opposite characteristics. Using these magnetic properties, a moisture content signal was extracted, even with Interference of the iron sand. © 2008 The Japan Society of Applied Physics.

DOI： 10.1143/APEX.1.067008

Magneto-electrical cyclic voltammetry for visualization of current distribution in the electrolyte

K. Tsukada, F. Kobayashi, H. Arai, T. Kiwa

Electrochemistry Communications 10 ( 6 ) 938 - 942 2008.6

Language：English Publisher：ELSEVIER SCIENCE INC

Cyclic voltammetry is widely used in electrochemistry. To visualize the current distribution in the electrolyte, we developed a two-dimensional magnetic imaging system, combining the electric measurement component used in conventional cyclic voltammetry with a pair of MR (magnetic resistive) sensors to detect the x- and y-magnetic components. The resulting system allows simultaneous measurement of the electronic current of the working electrode and the magnetic field resulting from the transport of ions by migration in the bulk electrolyte. The current distribution in the electrolyte was reconstructed using the magnetic field strength data obtained at multiple points. Consequently, we could observe the change in current distribution when changing the length of the working electrode immersed in the electrolyte. © 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.elecom.2008.04.020

Difference in the detection limits of flaws in the depths of multi-layered and continuous aluminum plates using low-frequency eddy current testing

Hironobu Yamada, Teruki Hasegawa, Yudai Ishihara, Toshihiko Kiwa, Keiji Tsukada

NDT and E International 41 ( 2 ) 108 - 111 2008.3

Language：English Publisher：ELSEVIER SCI LTD

We examined the difference in the detection limits of flaws in the depths of multi-layered and continuous aluminum plates using low-frequency eddy current testing. The detection limits were measured by using a magneto-resistive sensor. Comparing the frequency of an applied magnetic field, the detection limit at 50 Hz is deeper than that at 1 kHz. Comparing the sample structure, the detection limit in the multi-layered samples is deeper than that in the continuous samples. These results are likely due to the differences in the skin depth and conductivity of the sample. © 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ndteint.2007.08.004

Detection of the weak magnetic properties change of stainless-steel welding parts by low frequency magnetic imaging

Takayuki Hayashi, Hironobu Yamada, Toshihiko Kiwa, Keiji Tsukada, Masaji Tamazumi

Journal of Applied Physics 103 ( 7 ) 07E923 2008

Language：English Publisher：AMER INST PHYSICS

Differences in weld quality resulting from variations in welding conditions were detected via low frequency magnetic imaging. This magnetic imaging was obtained using a recently developed measurement system, consisting of an exposure coil, a magnetoresistive (MR) sensor, and a lock-in amplifier. A wide area of stainless-steel sample was exposed to the magnetic field via an induction coil, and the MR sensor measured the generated magnetic field from the sample. The frequency of the magnetic field ranged from 20 Hz to 1 kHz. A cylindrical stainless-steel sample was fabricated by rolling a stainless-steel sheet and welding each edge by an arc welder with argon gas, while the welding condition was changed by controlling the argon gas flow. The magnitude and phase shift of the generated magnetic field from the sample was measured by scanning the MR sensor on the sample surface. The change in magnetic properties caused by the welding condition change was successfully imaged. © 2008 American Institute of Physics.

DOI： 10.1063/1.2837628

Redox reactions of enzymes measured by terahertz chemical microscope

Toshihiko Kiwa, Jyunichi Kondo, Iwo Kawayama, Masayoshi Tonouchi, Keiji Tsukada

33rd International Conference on Infrared and Millimeter Waves and the 16th International Conference on Terahertz Electronics, 2008, IRMMW-THz 2008 594 - + 2008

Language：English Publisher：IEEE

A terahertz chemical microscope (TCM) was proposed and developed to measure redox reaction of enzymes. TCM utilize the sensing plate which can measure the surface potential changes at the laser illuminated area by detecting the terahertz waves generated from the plate. An immobilized urease was applied to the plate and the redox reaction with the urea in the buffer solution was demonstrated. @IEEE.

DOI： 10.1109/ICIMW.2008.4665724

テラヘルツ波ケミカル顕微鏡による流路内化学濃度分布イメージング

岡昇平, 近藤純一, 紀和利彦, 川山巌, 斗内政吉, 塚田啓二

応用物理学関係連合講演会講演予稿集 55th ( 3 ) 2008

磁場計測による電解質溶液中の電流評価

小林史幸, 新井裕之, 萬治寧大, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集 2008 ( 2 ) 2008

低周波磁気を用いたステンレス多層配管内の溶接部の新しい非破壊検出方法

林孝之, 林孝之, 川崎喜彦, 山田博信, 紀和利彦, 玉積正司, 塚田啓二

日本非破壊検査協会大会講演概要集 2008 2008

極低周波磁気を用いた鉄板溶接部の内部欠陥検査法

長谷川照起, 山田博信, 紀和利彦, 井上勝美, 玉積正司, 塚田啓二

日本非破壊検査協会大会講演概要集 2008 2008

パルス渦流探傷を用いたリフトオフの影響を受けない金属板厚み検査法の開発

川崎喜彦, 林孝之, 山田博信, 紀和利彦, 塚田啓二

日本磁気学会学術講演概要集 32nd 2008

低周波磁気検査によるステンレス多層配管中の溶接部の検出

林孝之, 林孝之, 川崎喜彦, 山田博信, 紀和利彦, 玉積正司, 塚田啓二

日本磁気学会学術講演概要集 32nd 2008

HTS-SQUID渦流探傷法による金属厚み検査装置の開発

紀和利彦, 田原秀哲, 山田博信, 塚田啓二

応用物理学会学術講演会講演予稿集 69th ( 1 ) 2008

各種ガスによるプロトンポンピングゲート水素センサのゲート部のインピーダンス変化

滝澤正教, 山口富治, 紀和利彦, 山田博信, 塚田啓二

電気学会全国大会講演論文集 2008 ( 3 ) 2008

低周波磁気イメージングシステムによるステンレス溶接欠陥の非破壊検査

林孝之, 林孝之, 山田博信, 紀和利彦, 玉積正司, 塚田啓二

電気学会全国大会講演論文集 2008 ( 2 ) 2008

フーリエ型パルス渦流探傷法による金属板厚検査法の開発

紀和利彦, 川崎喜彦, 林孝之, 山田博信, 塚田啓二

日本非破壊検査協会大会講演概要集 2008 2008

磁気による砂の水分含有量の測定方法

増田康孝, 紀和利彦, 塚田啓二

日本磁気学会学術講演概要集 32nd 2008

砂の水分量の新しい磁気計測方法

塚田啓二, 増田康孝, 石原雄大, 紀和利彦

応用物理学関係連合講演会講演予稿集 55th ( 1 ) 2008

交流変調時におけるプロトンポンピングゲートFET型水素センサの応答特性評価

山口富治, 滝澤正教, 紀和利彦, 山田博信, 塚田啓二

電気学会全国大会講演論文集 2008 ( 3 ) 2008

高温超伝導SQUIDを用いた高感度水分含有量測定システムの開発

田原秀哲, 三宅悦朗, 窪田篤, 紀和利彦, 山田博信, 塚田啓二

応用物理学関係連合講演会講演予稿集 55th ( 1 ) 2008

低周波渦流探傷検査システムの鉄板溶接部評価への適用

長谷川照起, 石原雄大, 林孝之, 紀和利彦, 山田博信, 塚田啓二

電気学会全国大会講演論文集 2008 ( 2 ) 2008

テラヘルツ波ケミカル顕微鏡によるガス選択検出手法の開発

小野坂宏之, 紀和利彦, 塚田啓二, 川山巌, 斗内政吉

電気学会全国大会講演論文集 2008 ( 3 ) 2008

THz波ケミカル顕微鏡を用いた酵素反応検出

紀和利彦, 川山巌, 斗内政吉, 塚田啓二

応用物理学会学術講演会講演予稿集 69th ( 3 ) 2008

THz波ケミカル顕微鏡を用いたガス触媒評価手法の開発

紀和利彦, 小野坂宏之, 川山巌, 山田博信, 斗内政吉, 塚田啓二

応用物理学関係連合講演会講演予稿集 55th ( 3 ) 2008

A terahertz chemical microscope to visualize chemical concentrations in microfluidic chips

Toshihiko Kiwa, Shohei Oka, Junichi Kondo, Iwao Kawayama, Hironobu Yamada, Masayoshi Tonouchi, Keiji Tsukada

Japanese Journal of Applied Physics, Part 2: Letters 46 ( 41-44 ) L1052 - L1054 2007.11

Language：English Publisher：JAPAN SOC APPLIED PHYSICS

Here, a new type of terahertz chemical microscope (TCM) is proposed and developed, and the first demonstration of imaging the chemical concentration in fluid channels is reported. Fluid samples flow through channels possessing a semiconductor sensing plate as a bottom wall. Terahertz (THz) waves are radiated from the sensing plate as a result of femtosecond laser illumination. Because the amplitude of the THz radiation depends on the concentration of ions adsorbed on the surface of the plate, the ion distribution in the fluid channels can be visualized by scanning the laser across the plate. An image showing separated solutions with two different proton concentrations is successfully observed as the first demonstration of this instrument. © 2007 The Japan Society of Applied Physics.

DOI： 10.1143/JJAP.46.L1052

A proton pumping gate field-effect transistor for a hydrogen gas sensor

Keiji Tsukada, Tomiharu Yamaguchi, Toshihiko Kiwa

IEEE Sensors Journal 7 ( 9 ) 1268 - 1269 2007.9

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

A proton pumping field-effect transistor (FET), consisting of a triple layer gate structure of a Pd/proton conducting polymer/Pt, has been developed. The hydrogen sensitivity was controlled by the bias change between Pt and Pd. Furthermore, two kinds of methods for the readout of DC and AC modulation can be achieved. According to the decrement of the bias frequency, the modulated output was increased. This characteristic realizes a gas sensor with a self-check function. © 2007 IEEE.

DOI： 10.1109/JSEN.2007.901268

Fourier-transformed eddy current technique to visualize cross-sections of conductive materials

Toshihiko Kiwa, Tomoaki Kawata, Hironobu Yamada, Keiji Tsukada

NDT and E International 40 ( 5 ) 363 - 367 2007.7

Language：English Publisher：ELSEVIER SCI LTD

A pulsed eddy current NDE system is useful for detecting deep flaws in conductive materials. We have developed a pulsed eddy current NDE system using a magneto-resistive sensor. The induction coil generates a pulsed magnetic field which has a frequency component between 0 and 3 kHz, and a maximum amplitude of about 4 μ T. Aluminum plates with flaws at depths of 1 and 2 mm were measured, and the intrinsic frequency responses of the plates were obtained using a proposed Fourier transformation method. Cross-sectional images of the samples could then be directly constructed from the intrinsic responses. We also demonstrated estimation of quantitative values for the depths of flaws. The estimated depth was well defined for a sample with a flaw at a depth of 2 mm. The estimated value was slightly different for a sample with a flaw at a depth of 1 mm due to lack of frequency components above 3 kHz. These results indicate that the proposed system is a very promising tool for NDE tomography. © 2007 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ndteint.2007.01.006

Detection of photomixing signals with a YBCO Josephson junction coupled to a coplanar waveguide

Iwao Kawayama, Ryuhei Kinjo, Toshihiko Kiwa, Hironaru Murakami, Masayoshi Tonouchi

IEEE Transactions on Applied Superconductivity 17 ( 2 ) 321 - 323 2007.6

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

We have fabricated a generation and detection system of photomixing signals using a photomixing technique and a Josephson junction detector. Up to now, an electromagnetic wave generated by a heterodyne mixing of two lasers was emitted from an antenna, and irradiated to a Josephson junction. In this study, we have developed the system, and the photomixing signal was introduced into a coaxial cable and a coplanar wave guide coupled to a Josephson junction. This structure is more suitable for device application since it can easily be integrated into electronic devices. With this system we can clearly observed photomixing signals from 16 GHz to 95 GHz using a uni-traveling-carrier photodiode as a photomlxer as well as signals in the range of 14 GHz to 50 GHz using an InGaAs PIN photodiode. © 2007 IEEE.

DOI： 10.1109/TASC.2007.898106

Magnetic measurement of moisture content of grain

Keiji Tsukada, Toshihiko Kiwa

IEEE Transactions on Magnetics 43 ( 6 ) 2683 - 2685 2007.6

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

We developed a technique to magnetically measure the moisture content of grain. The measurement method developed consists of an exposure magnetic coil, and a magnetic resistance sensor. When the grain is exposed to alternating magnetic fields of low frequency, a secondary magnetic field generated from the grain is observed. Two kinds of grain with different water absorption abilities (nonglutinous rice and glutinous rice) were measured. The secondary magnetic field strength of the grain increased incrementally with the moisture content. The experimental result indicated the applicability of the developed magnetic measurement method for nondestructive moisture measurement. © 2007 IEEE.

DOI： 10.1109/TMAG.2007.892853

Oxygen interference mechanism of platinum-FET hydrogen gas sensor

T. Yamaguchi, T. Kiwa, K. Tsukada, K. Yokosawa

Sensors and Actuators, A: Physical 136 ( 1 ) 244 - 248 2007.5

Language：English Publisher：ELSEVIER SCIENCE SA

This paper reports the effect of oxygen in air on a Pt-FET hydrogen sensor. The output voltage change of the Pt-FET had good linearity to the logarithm of hydrogen concentration in nitrogen. The slope of the linear curve is -26.4 mV/decade, which is close to the calculated value of the Nernstian slope. This indicates the response mechanism of the Pt-FET sensor is based on the catalytic reaction on the Pt surface. However, the output voltage change of the Pt-FET was not proportional to the logarithm of hydrogen concentration in air due to adsorbed oxygen on the Pt surface. This indicates the water formation for the reaction of hydrogen and oxygen on the Pt surface is the main hydrogen response mechanism in air. © 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.sna.2006.11.026

Study on sub-THz signal input for superconducting electronic devices

Iwao Kawayama, Yasushi Doda, Ryuhei Kinjo, Toshihiko Kiwa, Hironaru Murakami, Masayoshi Tonouchi

IEICE Transactions on Electronics E90-C ( 3 ) 588 - 594 2007.3

Language：English Publisher：IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG

Development of ultrafast optical interfaces that can operate in sub-terahertz region is important to apply superconducting electronic devices to the high-end systems. We have performed several fundamental researches to realize the ultrafast optical input interface for superconducting electronic devices. Firstly, we observed optical response of amorphous Ge thin films, and the results indicated that an amorphous Ge photoconductive switch could stably operate in a terahertz frequency range as an optical-to-electrical signal converter in the low-temperature region below Tc of YBCO. Next, we have fabricated optical-to-electrical signal conversion system with photomixing technique, and we have demonstrated the generation and the detection of high frequency signals over 50 GHz. Finally, we have observed optical responses of a Josephson vortex flow transistor under irradiation of femtosecond laser pulses, and the results suggeste that the device has high potential as an optical interface. Copyright © 2007 The Institute of Electronics, Information and Communication Engineers.

DOI： 10.1093/ietele/e90-c.3.588

Laser-terahertz emission from the chemical sensing plate

Toshihiko Kiwa, Junichi Kondo, Shohei Oka, Iwao Kawayama, Hironobu Yamada, Masayoshi Tonouchi, Keiji Tsukada

2007 JOINT 32ND INTERNATIONAL CONFERENCE ON INFRARED AND MILLIMETER WAVES AND 15TH INTERNATIONAL CONFERENCE ON TERAHERTZ ELECTRONICS, VOLS 1 AND 2 Vol. 1 pp. 285-286 280 - + 2007

Language：English Publisher：IEEE

A new type of sensing system to measure the concentration of the protons in the solutions by means of the laser-terahertz emission and detection was proposed and developed. The simple layered structures of SiO2/Si thin films on a sapphire substrate were prepared as a chemical sensing plate. The system measure the amplitude of the terahertz emission from the depletion layer of SiO2/Si interface by irradiating the femtosecond laser pulses with the center wavelength of 790 nm. The solution was contacted with the SiO2 surface and the Si thin film layer was electrically grounded. An Ag/AgCl reference electrode was used to control the potential of the solution. When the proton was adsorbed on the surface of the plate, the surface electric dipole was formed at the surface, which changes the local field of the depletion layer. Thus the peak amplitude of terahertz emission was changed depending on the number of the proton adsorbed on the surface of the plate. Actually, we demonstrated that the peak amplitude of terahertz; emission from the sensing plate increased by increasing the pH values of the test solution when the bias voltage of the solution was 0 V. (pH values indicate the concentration of the proton in the solution) and the sensitivity was about 31 mu V/pH.

Low-frequency magnetic field detection for metal sensing

Toshihiko Kiwa, Tomoaki Kawata, Keiji Tsukada

International Journal of Applied Electromagnetics and Mechanics 25 ( 1-4 ) 447 - 451 2007

Language：English Publisher：IOS PRESS

A new type of magnetic field detection system, which can operate at a frequency below 1 kHz, is proposed and developed. The system consists of a 40-turn-coil to generate the magnetic field and a magneto resistive sensor to detect both the amplitude and the phase signal of the magnetic field induced by eddy-current and magnetization of the samples. The magnetic field detection of ferro- and non-magnetic samples using the system is demonstrated and discussed. © 2007 - IOS Press and the authors. All rights reserved.

DOI： 10.3233/jae-2007-745

Hydrogen response mechanism of a proton pumping gate FET gas sensor

Keiji Tsukada, Tomiharu Yamaguchi, Toshihiko Kiwa, Hironobu Yamada

Proceedings of IEEE Sensors 1326 - 1329 2007

Language：English Publisher：IEEE

We developed a new type hydrogen sensor for a proton pumping gate FET with a triple layer of Pd / proton conducting polymer / Pt. Compared with conventional type FET with a single catalytic metal gate, the selectivity was improved. Furthermore, two different output signals of DC and AC modulation were obtained. According to increments of the upper gate voltage to a lower gate, the sensitivity was increased. When modulation voltage was added to the upper gate voltage, AC modulation output was obtained. The response mechanism of the new type FET was investigated using several hydrogen gases and with modulation conditions. Consequently, the hydrogen response mechanism can be explained by a hydrogen dissociation reaction occurring at the upper gate, and the hydrogen gas and generated proton can pass through the proton conducting polymer, and finally an equilibrium hydrogen reaction occurs at the lower gate. These complex mechanisms can be controlled by the gate bias and modulation voltage. © 2007 IEEE.

DOI： 10.1109/ICSENS.2007.4388655

Laser-terahertz emission from the chemical sensing plate

Toshihiko Kiwa, Junichi Kondo, Shohei Oka, Iwao Kawayama, Hironobu Yamada, Masayoshi Tonouchi, Keiji Tsukada

IRMMW-THz2007 - Conference Digest of the Joint 32nd International Conference on Infrared and Millimetre Waves, and 15th International Conference on Terahertz Electronics 285 - 286 2007

Language：English Publisher：IEEE

A new type of sensing system to measure the concentration of the protons in the solutions by means of the laser-terahertz emission and detection was proposed and developed. The simple layered structures of SiO2/Si thin films on a sapphire substrate were prepared as a chemical sensing plate. The system measure the amplitude of the terahertz emission from the depletion layer of SiO2/Si interface by irradiating the femtosecond laser pulses with the center wavelength of 790 nm. The solution was contacted with the SiO 2 surface and the Si thin film layer was electrically grounded. An Ag/AgCl reference electrode was used to control the potential of the solution. When the proton was adsorbed on the surface of the plate, the surface electric dipole was formed at the surface, which changes the local field of the depletion layer. Thus the peak amplitude of terahertz emission was changed depending on the number of the proton adsorbed on the surface of the plate. Actually, we demonstrated that the peak amplitude of terahertz emission from the sensing plate increased by increasing the pH values of the test solution when the bias voltage of the solution was 0 V. (pH values indicate the concentration of the proton in the solution) and the sensitivity was about 31 μV/pH.

DOI： 10.1109/icimw.2007.4516500

Laser-terahertz emission readout of chemical sensors

T. Kiwa, J. Kondo, S. Oka, I. Kawayama, H. Yamada, M. Tonouchi, K. Tsukada

TRANSDUCERS and EUROSENSORS '07 - 4th International Conference on Solid-State Sensors, Actuators and Microsystems Vol. 2, p.1915-1918, 2007 1915 - 1918 2007

Language：English Publisher：IEEE

A new type of laser-terahertz emission system for the non-contact investigation of the chemical solutions has been developed. This system monitors the terahertz emission from a sensing plate, which consists of a silicon oxide and a silicon thin film layers on the sapphire substrate. The sensing of chemical solutions with the pH value between 1.68 and 10.01 was demonstrated. The amplitude of terahertz emission from the sensing plate increased with increasing the pH value. This change in the amplitude was caused by the change of the depletion layers of the silicon thin film when protons adsorbed at the surface of the sensing plate. This result indicates that fully non-contact monitoring of chemical solutions can be possible using the laser-terahertz emission system. ©2007 IEEE.

DOI： 10.1109/SENSOR.2007.4300533

低周波渦流探傷検査システムの金属溶接部評価への適用

長谷川照起, 石原雄大, 林孝之, 山田博信, 紀和利彦, 塚田啓二

電気学会基礎・材料・共通部門大会講演論文集(CD-ROM) 2007 2007

FET型水素センサのガス選択性改善

山口富治, 滝澤正教, 紀和利彦, 山田博信, 塚田啓二

電気学会全国大会講演論文集 2007 ( 3 ) 2007

パルス渦流探傷によるフーリエ解析手法の開発

紀和利彦, 河田知明, 山田博信, 塚田啓二

電気学会全国大会講演論文集 2007 ( 2 ) 2007

プロトンポンピングゲート構造をもったFET型水素センサ

塚田啓二, 山口富治, 紀和利彦, 山田博信

電気学会全国大会講演論文集 2007 ( 3 ) 2007

Response Properties of Proton Pumping Gate FET Hydrogen Gas Sensor

山口富治, 滝澤正教, 紀和利彦, 山口博信, 塚田啓二

電気学会ケミカルセンサ研究会資料 CHS-07 ( 23-48 ) 2007

電解質溶液中のイオン輸送現象の磁気的解析

小林史幸, 新井裕之, 紀和利彦, 塚田啓二

日本応用磁気学会学術講演概要集 31st 2007

Pt-FET型水素センサの選択性評価

中田章太, 山口富治, 紀和利彦, 山田博信, 塚田啓二

電気学会全国大会講演論文集 2007 ( 3 ) 2007

低周波磁気検査によるステンレス溶接の欠陥評価

林孝之, 林孝之, 山田博信, 紀和利彦, 玉積正司, 塚田啓二

日本応用磁気学会学術講演概要集 31st 2007

テラヘルツ波を用いた非接触化学センサープレートの開発

紀和利彦, 近藤純一, 岡昇平, 川山巌, 山田博信, 斗内政吉, 塚田啓二

応用物理学関係連合講演会講演予稿集 54th ( 3 ) 2007

テラヘルツ波pHセンサーシステムの開発

近藤純一, 岡昇平, 紀和利彦, 山田博信, 塚田啓二, 川山巌, 斗内政吉

電気学会全国大会講演論文集 2007 ( 3 ) 2007

Measurement of hydrogen gas diffusion with FET sensors

吉武剣, 坪井公輔, 山口富治, 山田博信, 紀和利彦, 塚田啓二

電気学会ケミカルセンサ研究会資料 CHS-07 ( 23-48 ) 2007

穀物水分量の新しい磁気計測方法

塚田啓二, 紀和利彦

応用物理学関係連合講演会講演予稿集 54th ( 1 ) 2007

磁場計測を用いた新しい電気化学測定システムの開発

新井裕之, 小林史幸, 紀和利彦, 塚田啓二

電気学会基礎・材料・共通部門大会講演論文集(CD-ROM) 2007 2007

低周波磁気検査システムを用いた積層構造内部の欠陥評価

山田博信, 石原雄大, 紀和利彦, 塚田啓二, 玉積正司

電気学会全国大会講演論文集 2007 ( 1 ) 2007

低周波磁場照射による水の磁気応答特性

塚田啓二, 増田祐生, 紀和利彦

応用物理学関係連合講演会講演予稿集 54th ( 1 ) 2007

岡山大学大学院自然科学研究科電子情報システム工学専攻計測システム工学研究室

塚田啓二, 紀和利彦

電気学会論文誌. E, センサ・マイクロマシン準部門誌 = The transactions of the Institute of Electrical Engineers of Japan. A publication of Sensors and Micromachines Society 126 ( 11 ) 628 - 628 2006.11

AC magnetic properties of large volume of water - Susceptibility measurement in unshielded environment

Keiji Tsukada, Toshihiko Kiwa, Yuuki Masuda

Japanese Journal of Applied Physics, Part 2: Letters 45 ( 37-41 ) L1097 - L1099 2006.10

Language：English Publisher：JAPAN SOC APPLIED PHYSICS

To investigate the effect of low-frequency magnetic-field exposure of a human body, the low-frequency AC magnetic property of a large volume of water was measured by low-frequency magnetic field exposure (from 50 Hz to 1.2 kHz). The results indicate that the AC magnetic property of water is due to diamagnetism in the low-frequency range. The phase between the main magnetic field and the generated magnetic field remained constant at about 180°. Results were not affected by conductivity or pH. Moreover, the magnetic-field strength from water showed a susceptibility frequency dependence proportional to the frequency above approximately 400 Hz. Because of the incremental effects of susceptibility, the magnetic field from water was measured using a conventional magnetic sensor (magnetic resistive; MR) in an unshielded environment. ©2006 The Japan Society of Applied Physics.

DOI： 10.1143/JJAP.45.L1097

Low-frequency eddy current imaging using mr sensor detecting tangential magnetic field components for nondestructive evaluation

Keiji Tsukada, Toshihiko Kiwa, Tomoaki Kawata, Yudai Ishihara

IEEE Transactions on Magnetics 42 ( 10 ) 3315 - 3317 2006.10

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

An eddy-current distribution imaging system using a wide-area magnetic field exposure has been developed. This system can be employed to detect deep metal cracks using a magnetic resistive (MR) sensor. The measuring system consists of the exposure coil, MR sensors, measuring circuits, lock-in amplifier, xy stage, and a personal computer. To detect the eddy current distribution, the imaging system uses a pair of MR sensors that detect the x and y magnetic field components parallel to the metal surface. The system operates at a low-frequency range in order to obtain depth of penetration. An artificial defect consisting of a multilayer A1 substrate sample with a bottom half slit was measured to test the system. The change in the eddy current distribution image due to the presence of the flaw was obtained. In particular, it was determined that the detection of the slit depth was improved by this lower exposure frequency. © 2006, IEEE. All rights reserved.

DOI： 10.1109/TMAG.2006.879754

A study of fast response characteristics for hydrogen sensing with platinum FET sensor

K. Tsukada, T. Kiwa, T. Yamaguchi, S. Migitaka, Y. Goto, K. Yokosawa

Sensors and Actuators, B: Chemical 114 ( 1 ) 158 - 163 2006.3

Language：English Publisher：ELSEVIER SCIENCE SA

The fast response characteristics of a Pt-FET hydrogen sensor have been investigated using a hydrogen gas flow system and a flow-through cell for the sensor. The Pt-FET hydrogen sensor showed good linear response, detecting hydrogen concentrations from 10 ppm to 10%, and had a sensitivity of -25.1 mV/decade at room temperature, which is close to the value for the Nernstian slope. The transient response characteristic shows that the equivalent catalytic reaction on the platinum surface is dominant in the response time. © 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.snb.2005.04.026

Multipoint measurements of hydrogen gas using FET type hydrogen sensors

KIWA T.

Abstract of the 11th International Meeting on Chemical Sensors (IMCS11), 2006 2006

Magnetic property mapping system for analyzing three-dimensional magnetic components

Keiji Tsukada, Toshihiko Kiwa

Review of Scientific Instruments 77 ( 6 ) 2006

Language：English Publisher：AMER INST PHYSICS

A magnetic measurement system utilizing a vector magnetic sensor for analyzing and mapping low frequency magnetic properties of metals has been developed for nondestructive evaluation. The measurement system consists mainly of an induction coil which can expose a large sample area, a vector magnetic sensor for detecting magnetic fields emanating from a sample, a lock-in amplifier, and a two-dimensional scanning stage. The system was determined to have a high magnetic sensitivity corresponding to less than 1 nT in the locked-in state. The magnetic field strength change was detected in a sample that contained a slit of width greater than 1 mm. Time sequential vector component (normal and tangential) maps were developed. An iron plate as an example of a ferromagnetic metal and an aluminum plate as an example of a good conducting and nonferromagnetic material were compared using this system. Analyzing the vector component maps could differentiate differences in the magnetic properties, such as permeability, eddy current distribution, and residual magnetism. © 2006 American Institute of Physics.

DOI： 10.1063/1.2209949

最近の技術から集積回路評価用レーザーテラヘルツ放射顕微鏡の開発 ("開拓"進むテラヘルツ領域)

Hydrogen reaction characteristics of FET sensors with catalytic metal gate inhigy hydrogen concentration

K. Tsukada, T. Kiwa, T. Yamaguchi, K. Yokosawa

Proc. the 11the Int'l Meeting on Chemical Sensors (IMCS11, 16-19 July 2006) 2006

Humidity effect on the properties of FET-type hydrogen sensors

T. Kiwa, T. Yamaguchi, S. Nakada, K. Yokosawa, K. Tsukada

Proc. the 11the Int'l Meeting on Chemical Sensors (IMCS11, 16-19 July 2006) 2006

低周波磁場を用いた金属欠陥の2次元マッピング

河田知明, 山田博信, 紀和利彦, 塚田啓二

電気学会基礎・材料・共通部門大会(CD-ROM) 2006 2006

生体組織の磁気応答特性評価

宗行健太, 増田祐生, 紀和利彦, 塚田啓二

電気学会基礎・材料・共通部門大会(CD-ROM) 2006 2006

FET型水素センサによるガス濃度分布計測

吉武剣, 紀和利彦, 塚田啓二, 横沢宏一

電気学会全国大会講演論文集 2006 ( 3 ) 2006

FET型水素センサ応答特性の湿度影響評価

紀和利彦, 山口富治, 中田章太, 塚田啓二, 横沢宏一

電気学会全国大会講演論文集 2006 ( 3 ) 2006

低周波磁場欠陥検査手法の開発

石原雄大, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集 2006 ( 2 ) 2006

山下将嗣, 紀和利彦, 斗内政吉

光学 34 ( 9 ) 472 - 474 2005.9

Laser terahertz emission system to investigate hydrogen gas sensors

Toshihiko Kiwa, Keiji Tsukada, Masato Suzuki, Masayoshi Tonouchi, Sonoko Migitaka, Koichi Yokosawa

Applied Physics Letters 86 ( 26 ) 1 - 3 2005.6

Language：English Publisher：AMER INST PHYSICS

A laser terahertz emission system is proposed to investigate the catalytic metal/semiconductor interfaces of hydrogen sensors. Samples were fabricated by depositing a catalytic metal thin film on a semi-insulating silicon substrate. A femtosecond laser was used to radiate terahertz waves from the sample in a gas cell filled with a hydrogen and nitrogen gas mixture. The peak amplitude of the terahertz waves decreased with increasing hydrogen concentration. We also fabricated a metal-oxide-semiconductor field effect transistor hydrogen sensor, and compared its properties with the terahertz radiation properties. These results suggest that the laser terahertz emission system is a potential tool to investigate catalytic metal/semiconductor interfaces. © 2005 American Institute of Physics.

DOI： 10.1063/1.1954885

Imaging of large-scale integrated circuits using laser-terahertz emission microscopy. International journal

Masatsugu Yamashita, Kodo Kawase, Chiko Otani, Toshihiko Kiwa, Masayoshi Tonouchi

Optics express 13 ( 1 ) 115 - 20 2005.1

Language：English Publisher：OPTICAL SOC AMER

We present the redesign and improved performance of the laser terahertz emission microscope (LTEM), which is a potential tool for locating electrical failures in integrated circuits. The LTEM produces an image of the THz waves emitted when the circuit is irradiated by a femtosecond laser; the amplitude of the THz emission is proportional to the local electric field. By redesigning the optical setup and improving the spatial resolution of the system to below 3 microm, we could extend its application to examining of large-scale integration circuits. As example we show the THz emission pattern of the electric field in an 8-bit microprocessor chip under bias voltage.

DOI： 10.1364/OPEX.13.000115

Frequency detection of focused sub-THz waves using a high-T<inf>c</inf> Josephson junction

T. Miyadera, I. Kawayama, T. Kiwa, K. Tsukada, M. Tonouchi

Physica C: Superconductivity and its Applications 426-431 ( II ) 1726 - 1730 2005

Language：English Publisher：ELSEVIER SCIENCE BV

We have proposed a new type of frequency detection system of sub-terahertz electromagnetic waves using a photomixing technique and a Josephson junction detector. The photomixer illuminated by two lasers with different wavelengths generates coherent electromagnetic waves that include a frequency component corresponding to the frequency difference of the two lasers. The generated electromagnetic waves were radiated from a horn antenna and focused to the Josephson junction detector with Si lens. The high-Tc Josephson junction operates as a frequency detector for electromagnetic waves. Using this system, we observed the Shapiro steps of 188 μV that correspond to the frequencies of 90.8 GHz. © 2005 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physc.2005.02.136

Noninvasive measurements of magnetic field generated by induced current within human body under exposure to very low frequency electromagnetic fields

Keiji Tsukada, Toshihiko Kiwa

Japanese Journal of Applied Physics, Part 2: Letters 44 ( 16-19 ) L532 - L534 2005

Language：English Publisher：INST PURE APPLIED PHYSICS

We have developed a measurement system for a magnetic field that is generated by the induced ionic current within the human body under exposure to very low frequency electromagnetic fields, and compared the magnetic field strength obtained with those of a magnetomyogram (MMG). The developed system consists of an exposure coil, a magnetic sensor, a lock-in detector, and data acquisition. The waveform characteristics of the magnetic field of the induced current (MFIC) of the abdomen from 1 kHz to 400 Hz are obtained. Compared with the magnetic field strength of abdominal MMG, abdominal MFIC is stronger at an exposure electromagnetic field greater than the μ,T order. © 2005 The Japan Society of Applied Physics.

DOI： 10.1143/JJAP.44.L532

Spatial analysis of the three dimensional components of a magnetocardiogram

K. Tsukada, T. Kiwa, K. Ogata, T. Miyashita, A. Kandori

INTERMAG ASIA 2005: Digests of the IEEE International Magnetics Conference 620 2005

Terahertz emission properties from palladium/silicon interface

Toshihiko Kiwa, Keiji Tsukada, Masato Suzuki, Masayoshi Tonouchi, Sonoko Migitaka, Koichi Yokosawa

Digest of Technical Papers - International Conference on Solid State Sensors and Actuators and Microsystems, TRANSDUCERS '05 1 263 - 266 2005

Language：English Publisher：IEEE

Laser terahertz (THz) emission and detection system for investigating catalytic metal/semiconductor interface of the hydrogen sensors was proposed and developed. THz radiation from palladium/silicon structures was successfully obtained. The properties of THz radiation under hydrogen and nitrogen gas mixture were investigated. The peak amplitude of THz radiation was decreased by increasing the volume concentration of hydrogen gas. This change in the amplitude can be explained by change in the local field near the surface of silicon. This result indicates that the system is one of potential tool for non-destructive and non-contact measurement of the hydrogen sensors. © 2005 IEEE.

DOI： 10.1109/SENSOR.2005.1496407

水素ガスセンサの感応膜の特性評価

山口富治, 紀和利彦, 塚田啓二, 中野定樹, 右高園子, 横沢宏一

電気学会全国大会講演論文集 2005 ( 3 ) 2005

導波路結合型サブテラヘルツ電磁波発生・検出システムの開発

金城隆平, 宮寺達也, 川山巌, 村上博成, 紀和利彦, 塚田啓二, 斗内政吉

応用物理学関係連合講演会講演予稿集 52nd ( 1 ) 2005

テラヘルツ波を用いた水素センサー評価システムの構築

紀和利彦, 塚田啓二, 鈴木正人, 斗内政吉, 右高園子, 横沢宏一

応用物理学関係連合講演会講演予稿集 52nd ( 3 ) 2005

空間結合型サブテラヘルツ電磁波発生・検出システムの開発

川山厳, 宮寺達也, 村上博成, 紀和利彦, 塚田啓二, 斗内政吉

応用物理学関係連合講演会講演予稿集 52nd ( 1 ) 2005

テラヘルツ電磁波による水素センサー特性評価

紀和利彦, 塚田啓二, 鈴木正人, 斗内政吉, 右高園子, 横沢宏一

電気学会全国大会講演論文集 2005 ( 3 ) 2005

磁気センサーを用いた金属検出器の開発

河田知明, 紀和利彦, 塚田啓二

電気学会全国大会講演論文集 2005 ( 2 ) 2005

生体内誘導電流の磁気的計測方法

塚田啓二, 紀和利彦

日本ME学会大会論文集 44th 2005

磁気センサを用いた生体内誘導電流の計測

塚田啓二, 紀和利彦

電気学会全国大会講演論文集 2005 ( 2 ) 2005

低周波磁場照射による生体内の誘導電流の磁気的計測

塚田啓二, 紀和利彦

応用物理学関係連合講演会講演予稿集 52nd ( 1 ) 2005

THz time domain spectroscopy of pulsed laser deposited BaTiO <inf>3</inf> thin films

M. Misra, K. Kotani, T. Kiwa, I. Kawayama, H. Murakami, M. Tonouchi

Applied Surface Science 237 ( 1-4 ) 421 - 426 2004.10

Language：English Publisher：ELSEVIER SCIENCE BV

We have measured the dielectric properties of pulsed laser deposited 1.1μm thick BaTiO 3 (BTO) thin films on MgO substrate in the MHz and THz frequency region. The properties of two BTO thin films deposited at substrate temperature 790 and 840°C have been studied. X-ray diffraction pattern and AFM measurement of the films shows that the BTO film grown at temperature 840°C has better epitaxial growth and smooth surface compared to the film grown at 790°C. The dielectric properties of thin films have been measured by THz time domain spectroscopy (THz-TDS) in the frequency range from 0.3 to 2.5THz and by interdigital electrode measurement in the region from 10kHz to 10MHz. The BTO thin film deposited at higher temperature has a higher dielectric constant and tunability in the MHz frequency range whereas at THz frequencies the real and imaginary part of the refractive index and dielectric constant of both films show almost similar behavior. © 2004 Elsevier B.V. All rights reserved.

DOI： 10.1016/S0169-4332(04)01012-8

Ultrafast optical study of amorphous Ge thin films for superconductor/ semiconductor hybrid devices

T. Miyadera, T. Kiwa, I. Kawayama, H. Murakami, M. Tonouchi

Physica C: Superconductivity and its Applications 412-414 ( SPEC. ISS. ) 1602 - 1606 2004.10

Language：English Publisher：ELSEVIER SCIENCE BV

We investigated the optical response of amorphous (a-) Ge thin films by a time-resolved reflectivity measurement and the observation of terahertz radiation from a-Ge photoconductive switch coupled with Au/Cr transmission lines. The results show that the lifetime of photocarrier in the a-Ge is about 0.9 ps, and the pulse width of terahertz beam radiated from the photoconductive switch is about 1 ps. These results indicate that a-Ge can be used as an optical-to-electrical converter in sub-terahertz frequency range. However, the peak width of a-Ge photoconductive switches with YBCO transmission lines is about 2 ps and broad compared with the result with Au/Cr transmission lines. © 2004 Published by Elsevier B.V.

DOI： 10.1016/j.physc.2003.12.089

Real-time monitoring of a photomixing signal using a high-T<inf>C</inf> Josephson junction

Toshihiko Kiwa, Masayoshi Tonouchi

Superconductor Science and Technology 17 ( 8 ) 998 - 1002 2004.8

Language：English Publisher：IOP PUBLISHING LTD

An optical-microwave conversion system has been proposed as a high-stability oscillator in the microwave and millimetre-wave frequency region. A photomixer with heterodyne mixing of two lasers was applied to generate electromagnetic waves and a high-TC grain boundary Josephson junction detector was used to monitor the frequency of the electromagnetic waves in real time. We described the system in detail; it employed a sealed optical connector to introduce the optical signal directly into the cryostat.

DOI： 10.1088/0953-2048/17/8/008

Terahertz radiation from InAs/Al<inf>x</inf>Ga<inf>1-x</inf>Sb (x = 0.5) heterostructures

Masato Suzuki, Toshihiko Kiwa, Masayoshi Tonouchi, Yoji Nakajima, Shigehiko Sasa, Masataka Inoue

Physica E: Low-Dimensional Systems and Nanostructures 22 ( 1-3 ) 574 - 577 2004.4

Language：English Publisher：ELSEVIER SCIENCE BV

We observed terahertz radiation from InAs/Al0.5Ga 0.5Sb heterostructures excited by femtosecond pulses of mode-locked Ti:sapphire laser in the temperature range of 20-300 K. The radiation pseudo-reflected is monitored in time domain by a low temperature grown GaAs photoswitch. Although the waveforms are almost identical irrespective of temperatures, their maximum amplitude is strongly temperature dependent and peaks at around 100 K. Laser power dependence of the amplitude indicates that the excitation at power densities above 57 W/cm2 induce saturation presumably due to screening effect. © 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.physe.2003.12.073

An imaging and quantitative analysis technique for diagnosis of electro-pysiological excitation abnormality of heart

K. Tsukada, K. Ogata, T. Miyashita, S. Yamada, H. Horigome, J. Shiono, T. Kiwa, A. Kandori, I. Yamaguchi

Proceedings of the 14th International Conference on Biomagnetism 2004

A DEVELOPMENT OF MEASURING SYSTEM OF INDUCED CURRENT IN HUMAN BODY DUE TO LOW FREQUENCY ELECTROMAGNETIC IRRADIATION

Keiji Tsukada, Toshihiko Kiwa

Proceedings of Biological Effects of EMFs, 3rd International Workshop 2004

LSI故障解析用レーザーテラヘルツエミッション顕微鏡の開発レーザーテラヘルツエミッション顕微鏡による集積回路観察

山下将嗣, 紀和利彦, 斗内政吉, 二川清, 大谷知行, 川瀬晃道

マイクロファブリケーション研究の最新動向 15 2004

ジョセフソン接合を用いたフォトミキシング電磁波周波数検出・安定化システム

紀和利彦, 斗内政吉

応用物理学関係連合講演会講演予稿集 51st ( 3 ) 2004

運動負荷による心臓磁場変化の解析

塩田隆雄, 紀和利彦, 塚田啓二, 緒方邦臣, 宮下豪, 神鳥明彦

日本ME学会秋季大会論文集 18th 2004

光ファイバ結合型コンパクトテラヘルツ分光ヘッドの開発

大野恭裕, 紀和利彦, 斗内政吉

応用物理学関係連合講演会講演予稿集 51st ( 3 ) 2004

光ファイバ結合型コンパクトテラヘルツ分光システムの構築

大野恭裕, 井上亮太郎, 紀和利彦, 塚田啓二, 斗内政吉

応用物理学会学術講演会講演予稿集 65th ( 3 ) 2004

テラヘルツエミッション顕微鏡によるMOSトランジスタの非接触測定

山下将嗣, 紀和利彦, 斗内政吉, 二川清, 川瀬晃進

応用物理学関係連合講演会講演予稿集 51st ( 3 ) 2004

心臓磁場の空間解析

楠野順也, 紀和利彦, 塚田啓二, 緒方邦臣, 宮下豪, 神鳥明彦

日本ME学会秋季大会論文集 18th 2004

レーザーテラヘルツエミッション顕微鏡による集積回路観察

山下将嗣, 紀和利彦, 斗内政吉, 大谷知行, 川瀬晃道

レーザ顕微鏡研究会講演会抄録集 30th 2004

チューナブルサブテラヘルツ電磁波発生・検出システム

宮寺達也, 川山巌, 紀和利彦, 塚田啓二, 斗内政吉

応用物理学会学術講演会講演予稿集 65th ( 1 ) 2004

レーザーテラヘルツ放射顕微鏡

斗内政吉, 紀和利彦, 山下将嗣, 川瀬晃道

応用物理学関係連合講演会講演予稿集 51st ( 0 ) 2004

高温超伝導体におけるポンプ・プローブテラヘルツ電磁波励起観測

寺坂宏介, 富成征弘, 高橋宏平, 紀和利彦, 村上博成, 斗内政吉

応用物理学関係連合講演会講演予稿集 51st ( 1 ) 2004

心磁の3次元ベクトル成分解析

増田祐生, 紀和利彦, 塚田啓二, 緒方邦臣, 宮下豪, 神鳥明彦

日本ME学会秋季大会論文集 18th 2004

Generation of sub-terahertz waves using a semiconductor photomixer

Toshihiko Kiwa, Hironaru Murakami, Masayoshi Tonouchi

Superconductor Science and Technology 16 ( 12 ) 1540 - 1543 2003.12

Language：English Publisher：IOP PUBLISHING LTD

A low-temperature-grown GaAs (LT-GaAs) photoconductive switch has been utilized as a photomixer in the sub-terahertz (sub-THz) region. The usefulness of the switch has been demonstrated by detecting the radiated sub-THz wave with a high-TC Josephson junction detector consisting a series of nine junctions and a gold-coated log-periodic antenna. The sub-THz waves are radiated from the photoconductive switch by introducing the optical heterodyne signal of two semiconductor lasers. Although the radiation power of the photoconductive switch is three orders of magnitude lower than a conventional photodiode, the sub-THz waves from the switch were successfully observed in the difference voltage response of the junctions. This result suggests that the LT-GaAs switch can be used as the photomixer in the optical-microwave converter for superconductive electronics. We have also studied the properties of a radiated sub-THz frequency spectrum using a Martin-Puplett interferometer.

DOI： 10.1088/0953-2048/16/12/048

Optical response of amorphous Ge photoconductive switches with YBCO transmission lines

I. Kawayama, T. Miyadera, Y. Doda, T. Kiwa, H. Murakami, M. Tonouchi

Superconductor Science and Technology 16 ( 12 ) 1475 - 1478 2003.12

Language：English Publisher：IOP PUBLISHING LTD

Amorphous germanium (a-Ge) photoconductive switches coupled with YBCO transmission lines are fabricated on MgO (100) substrates. The optical responses of the photoconductive switches at lower temperatures are examined using the terahertz beam generation technique. The results have revealed that the a-Ge photoconductive switch can stably work at low temperatures and operation frequencies around 100 GHz. We also discuss the effects of YBCO transmission lines and the deterioration of the interface between a-Ge and YBCO.

DOI： 10.1088/0953-2048/16/12/034

Laser terahertz-emission microscope for inspecting electrical faults in integrated circuits. International journal

Toshihiko Kiwa, Masayoshi Tonouchi, Masatsugu Yamashita, Kodo Kawase

Optics letters 28 ( 21 ) 2058 - 60 2003.11

Language：English Publisher：OPTICAL SOC AMER

A laser terahertz-emission microscope (LTEM) system is proposed and developed for inspecting electrical faults in integrated circuits (IC). We test a commercial operational amplifier while the system is operating. Two-dimensional terahertz-emission images of the IC chip are clearly observed while the chip is scanned with a femtosecond laser. When one of the interconnection lines is cut, the damaged chip has a LTEM image different from that of normal chips. The results indicate that the LTEM system is a potential tool for IC inspection.

DOI： 10.1364/OL.28.002058

Characteristics of superconducting flux flow transistors under irradiation of femtosecond laser pulses

Y. Doda, T. Kiwa, I. Kawayama, H. Murakami, M. Tonouchi

Physica C: Superconductivity and its Applications 392-396 ( PART 2 ) 1504 - 1508 2003.10

Language：English Publisher：ELSEVIER SCIENCE BV

We have fabricated superconducting flux flow transistors with YBCO thin films and investigated the vortex flow characteristics under the irradiation of femtosecond laser pulses. The vortex flow velocity was calculated by the magnetic field dependence of the flow voltage. The obtained velocity without laser irradiation is 0.08-1.37 × 104 m/s for the bias current IB = 0.4-0.8 mA. The flow voltage increased gradually when the irradiated laser power was up to 10 mW, however, it increased drastically when the laser power was more than 10 mW. The maximum velocity of 6.3 × 10 4 m/s was obtained at the laser power of 15 mW. The result indicates that the laser pulses excite the vortices and accelerate the vortex velocity. © 2003 Elsevier B.V. All rights reserved.

DOI： 10.1016/S0921-4534(03)00779-2

Terahertz Radiation from InAs/AlGaSb heterostructures

Suzuki M., Kiwa T., Tonouchi M., Nakajima Y., Sasa S., Inoue M.

Meeting abstracts of the Physical Society of Japan 58 ( 2 ) 657 - 657 2003.8

THz radiation properties of Tl<inf>2</inf>Ba<inf>2</inf>CaCu<inf>2</inf>O<inf>8+δ</inf> thin films excited by femtosecond laser pulses

Yukihiro Tominari, Toshihiko Kiwa, Hironaru Murakami, Masayoshi Tonouchi, Henrik Schneidewind, Hagen Wald, Paul Seidel

IEEE Transactions on Applied Superconductivity 13 ( 2 III ) 3730 - 3732 2003.6

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Previously, we found the resonant THz wave radiation from c-axis oriented underdoped Tl2Ba2CaCu2O8+δ (Tl-2212) thin films by femtosecond laser pulse illumination under magnetic field. The properties of the resonant THz wave were well explained by the Josephson plasma resonance phenomenon. In the present study, the THz radiation properties were investigated for an overdoped Tl-2212 thin films. The amplitudes of THz waveform radiated under a bias current condition is much smaller than those of previous sample, while any trace of resonant THz signals could not be observed under magnetic field. These experimental results indicate the possibility that the initial THz wave radiated by ultrafast modulation in eddy-current around the vortices has an important role to excite the collective mode oscillation.

DOI： 10.1109/TASC.2003.812529

Backscattered terahertz radiation imaging system to visualize supercurrent distributions

T. Kiwa, Y. Kamata, M. Misra, H. Murakami, M. Tonouchi

IEEE Transactions on Applied Superconductivity 13 ( 2 III ) 3675 - 3678 2003.6

Language：English Publisher：IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

A new type of terahertz (THz) radiation imaging has been proposed and demonstrated. The supercurrent distributions were visualized by detecting the backscattered THz radiation from optically excited high-temperature superconductors. The supercurrent distributions were clearly observed in 100- and 500-nmthick YBa2Cu3O7-δ films in the remanent state. Our system has performance similar to the system with transmission configuration.

DOI： 10.1109/TASC.2003.812428

Coherent terahertz radiation from Tl<inf>2</inf>Ba<inf>2</inf>CaCu<inf>2</inf>O<inf>8+δ</inf> thin films excited by optical laser pulse under magnetic field

Yukihiro Tominari, Toshihiko Kiwa, Hironaru Murakami, Masayoshi Tonouchi, Hagen Wald, Paul Seidel, Henrik Schneidewind

Physica C: Superconductivity and its Applications 388-389 481 - 482 2003.5

Language：English Publisher：ELSEVIER SCIENCE BV

We observed terahertz (THz) pulse radiation from Tl2Ba2CaCu2O8+δ thin films by femtosecond optical pulse excitation under a bias-current condition and a radial magnetic field of ∼100 Oe nearly parallel to the c-axis of the film. The observed waveform under magnetic field showed clear oscillations below 80 K, and the Fourier spectrum showed an additional peak other than the frequency components observed in the bias-current condition. The additional peak (630 GHz at 24 K) shifted towards lower frequency region with increasing temperature. The observed resonant THz wave behavior is quantitatively explained by Josephson plasma phenomenon. © 2003 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0921-4534(02)02589-3

THz imaging of supercurrent distribution in Meissner state of LPE-BSCCO film

H. Murakami, T. Kiwa, M. Tonouchi, T. Yasuda

Physica C: Superconductivity and its Applications 388-389 479 - 480 2003.5

Language：English Publisher：ELSEVIER SCIENCE BV

The terahertz (THz) imaging system applicable to bulk or thick superconductors was developed. The supercurrent distribution in Bi2Sr2CaCu2O8+δ (BSCCO) thick film in Meissner state was observed. The experimental technique and the results obtained on a liquid phase epitaxy grown (LPE-)BSCCO thick film were presented. The resistive measurement showed the critical temperature of about 75 K.

DOI： 10.1016/S0921-4534(02)02588-1

Photomixing Optical-Microwave Transformer Coupled with High-T_C Josephson Junctions.

紀和利彦, 斗内政吉

低温工学 38 ( 1 ) 2003

後方散乱型テラヘルツ電磁波イメージングによる半導体IC断線評価

紀和利彦, 斗内政吉

応用物理学関係連合講演会講演予稿集 50th ( 3 ) 2003

フォトミキシング光-マイクロ波変換システム (II)

紀和利彦, 村上博成, 斗内政吉

応用物理学会学術講演会講演予稿集 64th ( 1 ) 2003

フォトミキシング電磁波のジョセフソン接合直列アレイによる検出

紀和利彦, 村上博成, 斗内政吉

応用物理学関係連合講演会講演予稿集 50th ( 1 ) 2003

非晶質Ge薄膜の高速光応答計測

宮寺達也, 紀和利彦, 川山巌, 斗内政吉

光物性研究会論文集 14th 2003

Study on Optical Response of Amorphous Ge Thin Films for Superconductor-Semiconductor Hybrid Optical Interface

宮寺達也, 紀和利彦, 川山巌, 村上博成, 斗内政吉

電子情報通信学会技術研究報告 103 ( 367(SCE2003 19-27) ) 2003

Photomixer/High-T_C Josephon Junction Hybrid System

紀和利彦, 鈴木正人, 村上博成, 斗内政吉

電子情報通信学会技術研究報告 103 ( 367(SCE2003 19-27) ) 2003

IC断線評価システムの空間分解能評価

山下将嗣, 紀和利彦, 川瀬晃道, 斗内政吉

応用物理学会学術講演会講演予稿集 64th ( 3 ) 2003

YBa₂Cu₃O_7-x薄膜を伝送線に持つ非晶質Ge光スイッチの低温特性

宮寺達也, 紀和利彦, 川山巌, 村上博成, 斗内政吉

応用物理学関係連合講演会講演予稿集 50th ( 1 ) 2003

Relaxation dynamics of optically excited quasi-particles in BSCCO

H. Murakami, T. Yasuda, Y. Tominari, T. Kiwa, M. Tonouchi, T. Uchiyama, I. Iguchi, Z. Wang

Physica C: Superconductivity and its Applications 378-381 ( PART 1 ) 320 - 323 2002.10

Language：English Publisher：ELSEVIER SCIENCE BV

To investigate the multi-excitation processes on the low-lying electronic structure of high-TC superconductors, time-domain pump and probe measurement has been carried out on under- and over-doped Bi2Sr2CaCu2O8+δ films. In the underdoped film, we found evidence for coexistence of two excitation states due to superconducting gap Δs and pseudogap Δp below TC. The observed relaxation processes of optically excited quasi-particles were well explained by two relaxation times of T-dependent τs and almost T-independent τp (0.7 ± 0.3 ps below 150 K). The τp existed up to T* ∼ 200 K and disappeared above 225 K. On the other hand, only one relaxation time, τs, was observed in the overdoped film at T = 10 K. The relaxation time, τs=4.2 ± 0.3 ps (below 40 K), for the underdoped sample was shorter than τs = 5.9 ± 0.2 ps (at T = 10 K) for the overdoped one, and about two times longer than τs = 2.1 ± 0.1 ps for YBa2Cu3O7-δ thin film. © 2002 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0921-4534(02)01435-1

Partial and macroscopic phase coherences in an underdoped Bi<inf>2</inf>Sr<inf>2</inf>CaCu<inf>2</inf>O<inf>8+δ</inf> thin film

H. Murakami, T. Kiwa, N. Kida, M. Tonouchi, T. Uchiyama, I. Iguchi, Z. Wang

Europhysics Letters 60 ( 2 ) 288 - 294 2002.10

Language：English Publisher：E D P SCIENCES

A combined study using the time-resolved pump-probe technique and the time domain terahertz transmission spectroscopy has been carried out to investigate the normal-state anomalies in underdoped Bi2Sr2CaCu2O8+δ. It was observed that a superconducting gap and a pseudogap coexist in the superconducting state. The pseudogap locally evolves below T* ≃ 210 K simultaneously with the appearance of partial phase coherence with a short lifetime less than 1 ps. With decreasing temperature, the domains with a pseudogap developed and saturated at TS ∼ 95 K, and the frequency-dependent superconductivity fluctuation appeared as cooperative phenomena among the partial phase-coherent domains. These experimental data show that the development of the partial coherent local domains with a pseudogap has an important role to switch from the partial to the macroscopic phase-coherent state.

DOI： 10.1209/epl/i2002-00349-x

Resonant terahertz radiation from Tl<inf>2</inf>Ba<inf>2</inf>CaCu <inf>2</inf>O<inf>8+δ</inf> thin films by ultrafast optical pulse excitation

Yukihiro Tominari, Toshihiko Kiwa, Hironaru Murakami, Masayoshi Tonouchi, Hagen Wald, Paul Seidel, Henrik Schneidewind

Applied Physics Letters 80 ( 17 ) 3147 - 3149 2002.4

Language：English Publisher：AMER INST PHYSICS

We have observed the free-space radiation of the resonant terahertz wave from c-axis oriented Tl2Ba2CaCu2O 8+δ thin films by femtosecond optical pulse excitation under a radial magnetic field of about 100 Oe nearly parallel to the c axis of the thin film. The observed wave form showed clear oscillations up to 80 K. The frequency was shifted from ∼620GHz at 24 K to ∼300GHz at 80 K, corresponding to an increase in c-axis penetration depth, λc, from ∼26μm to ∼53μm, and disappeared above TC as expected for the Josephson plasma resonance. © 2002 American Institute of Physics. © 2002 American Institute of Physics.

DOI： 10.1063/1.1475770

Tetrahertz pulse radiation properties of a Bi<inf>2</inf>Sr<inf>2</inf>CaCu<inf>2</inf>O<inf>8+δ</inf> bowtie antenna by optical pulse illumination

Hironaru Murakami, Toshihiko Kiwa, Muku L. Misra, Masayoshi Tonouchi, Tetsuji Uchiyama, Ienari Iguchi, Zhen Wang

Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 41 ( 4 ) 1992 - 1997 2002.4

Language：English Publisher：INST PURE APPLIED PHYSICS

We demonstrate, for the first time, terahertz (THz) pulse radiation properties from a current biased Bi2Sr2CaCu2O8+δ (BSCCO) bowtie antenna by femtosecond laser pulse illumination. The bias current, excitation laser power and temperature dependence of the radiated amplitude of THz pulse are basically in good agreement with those observed on YBa2Cu3O7-δ (YBCO). However, the detailed properties of the THz pulse from BSCCO are considerably different from those for YBCO. The observed amplitude of the terahertz (THz) radiation pulse was very strong due to the small index value of BSCCO thin film even for the small bias current, and the Fourier components of the pulse contains the frequencies lower than 0.4 THz with a central frequency around 0.1-0.16 THz reflecting its long relaxation time of photo-excited quasi-particle in BSCCO.

DOI： 10.1143/jjap.41.1992

25aYH-10 Optically excited Josephson plasma emission of THz-wave from Tl_2Ba_2CaCu_2O_<8+δ> thin films

Tominari Y., Kiwa T., Murakamic H., Tonouchi M., Wald H., Seidel P., Schneidewind H.

Meeting abstracts of the Physical Society of Japan 57 ( 1 ) 546 - 546 2002.3

24pYK-11 Ultrafast carrier dynanics in pseudgap state of BSCCO

Murakami H., Kiwa T., Tonouchi M., Uchiyama T., Iguchi I., Wang Z., Yasuda T.

Meeting abstracts of the Physical Society of Japan 57 ( 1 ) 506 - 506 2002.3

Preparation and picosecond optical response of Bi system high-T<inf>c</inf> superconductors

Yukihiro Tominari, Toshihiko Kiwa, Hironaru Murakami, Masayoshi Tonouchi, Takeshi Arai, Takafumi Aomine

Physica C: Superconductivity and its Applications 367 ( 1-4 ) 332 - 336 2002.2

Language：English Publisher：ELSEVIER SCIENCE BV

Bi2Sr2Ca1-xYxCu2 O8+δ single crystals were grown by traveling solvent floating zone method. The crystallinity and the superconducting property of the single crystals were characterized by X-ray diffraction and in-plane resistivity measurements. To investigate the ultrafast optical response, time-resolved pump-probe reflectivity measurements were carried out on the single crystals. As a result, fairly long relaxation times of about 20 and 6 ps of excited carriers were estimated for the crystals with x=0 and 0.2, respectively, as compared to 1.7 ps for YBa2Cu3O7-δ thin films in previous study. The relaxation time observed on the underdoped crystal with x=0.2 showed a good consistency with that of Bi2Sr2CaCu2O8+δ thin film in underdoped regime. © 2002 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0921-4534(01)01027-9

Time-domain terahertz spectroscopy of Bi<inf>2</inf>Sr<inf>2</inf>CaCu<inf>2</inf>O<inf>8+δ</inf> thin film

Hironaru Murakami, Toshihiko Kiwa, Masayoshi Tonouchil, Tetsuji Uchiyama, Ienari Iguchi, Zhen Wang

Physica C: Superconductivity and its Applications 367 ( 1-4 ) 322 - 326 2002.2

Language：English Publisher：ELSEVIER SCIENCE BV

Time-domain terahertz (THz) spectroscopy was carried out on a c-axis oriented Bi2Sr2CaCu2O8+δ (BSCCO) thin film. We extracted various optical parameters at frequencies from 0.3 to 1.0 THz and temperatures from 5 to room temperature by numerically solving the observed complex transmittance without Kramers-Kronig analysis. As a result, the frequency dependence of surface resistance RS showed different power laws of RS∝f (f<0.5 THz) and RS∝f1/2 (0.5 THz <f) in the superconducting state. Below the characteristic frequency, fC≃0.5 THz, rapid increase in the density of supercarrier, NS, was obtained. These obtained results well explained the electromagnetic-wave radiation property which had been observed on the same BSCCO thin film. © 2002 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0921-4534(01)01025-5

TERAHERTZ EMISSION PROPERTIES OF JOSEPHSON JUNCTION UNDER SMALL MAGNETIC FIELD

T. Kiwa, T. Yoshimura, H. Murakami, M. Tonouchi

Singapore Journal of Phsycis 2002

Terahertz Radiation from Strongly Correlated Electron Systems and Related Phenomena.

斗内政吉, 貴田徳明, 紀和利彦, 富成征弘, 川山巌, 村上博成

レーザー研究 30 ( 7 ) 2002

フォトミキシング光-マイクロ波変換システム

紀和利彦, 村上博成, 斗内政吉

応用物理学会学術講演会講演予稿集 63rd ( 1 ) 2002

フェムト秒レーザー照射によるフラックスフロートランジスタのフロー特性の変化

堂田泰史, 紀和利彦, 川山巌, 村上博成, 斗内政吉

応用物理学会学術講演会講演予稿集 63rd ( 1 ) 2002

超短光パルス励起によるTl₂Ba₂CaCu₂O_8+δ薄膜からのTHz電磁波放射特性

村上博成, 富成征弘, 紀和利彦, 斗内政吉, WALD H, SEIDEL P, SCHNEIDEWIND H

応用物理学関係連合講演会講演予稿集 49th ( 1 ) 2002

Time-resolved pump and probe reflection spectroscopy of Y-doped BSCCO single crystal

Tominari Y., Kiwa T., Murakami H., Tonouchi M., Arai T., Aomine T., Yasuda K.

Meeting abstracts of the Physical Society of Japan 56 ( 2 ) 424 - 424 2001.9

Time-domain THz Spectroscopy of BSCCO Thin Film

Murakami H., Kiwa T., Tonouchi M., Uchiyama T., Iguchi I., Wang Z.

Meeting abstracts of the Physical Society of Japan 56 ( 2 ) 441 - 441 2001.9

High frequency properties of YBCO thin films diagnosed by time-domain terahertz spectroscopy

Toshihiko Kiwa, Masayoshi Tonouchi

Physica C: Superconductivity and its Applications 362 ( 1-4 ) 314 - 318 2001.9

Language：English Publisher：ELSEVIER SCIENCE BV

We measure the complex conductivity σ and the surface impedance of c-axis oriented 100-nm-thick YBa2Cu3O7-δ (YBCO) thin films deposited on (100)MgO substrates (0.5 mm thick) at frequencies between 0.5 and 1.5 THz, using time-domain terahertz spectroscopy. The real part of σ decreases with increasing frequency and its value is about 2.4×105 (S/m) at 1 THz. The imaginary part of σ increases with increasing frequency and then monotonically decreases at around 750 GHz. The real part of σ of YBCO thin films increased with decreasing temperature and decreases below 60 K. The imaginary part of σ increased with decreasing temperature and the trend is enhanced below 60 K. The surface resistance of YBCO thin film is of the order of 10-1Ω and increases with increasing temperature. The surface reactance of YBCO thin film is independent of the frequency in this THz region, and its value is less than 10-3Ω at 40 K. © 2001 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0921-4534(01)00695-5

Terahertz emission from YBa<inf>2</inf>Cu<inf>3</inf>O<inf>7-δ</inf> Josephson junctions excited by femtosecond laser

Takahiro Yoshimura, Toshihiko Kiwa, Masayoshi Tonouchi

Physica C: Superconductivity and its Applications 362 ( 1-4 ) 329 - 332 2001.9

Language：English Publisher：ELSEVIER SCIENCE BV

We examine both power and bias current dependence of terahertz (THz) emission properties from YBa2Cu3O7-δ (YBCO) Josephson junctions. The junctions coupled to bow-tie antennas are fabricated by Ar ion milling from YBCO thin films grown on MgO bicrystals. We observe the radiation at bias currents from 0 to 50 mA, laser powers from 0 to 250 mW. The radiation amplitude increases with increasing laser power, and the frequency at which the radiation has a maximum amplitude decreases with increasing laser power. These trends are observed regardless of junction voltage. The results suggest that the voltage of the Josephson junction plays a less important role in the THz radiation excited by a femtosecond laser. © 2001 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0921-4534(01)00698-0

Terahertz emission properties from YBCO thin film log-periodic antennas

Hitoshi Saijo, Masahiko Morimoto, Toshihiko Kiwa, Masayoshi Tonouchi

Physica C: Superconductivity and its Applications 362 ( 1-4 ) 319 - 323 2001.9

Language：English Publisher：ELSEVIER SCIENCE BV

We study terahertz (THz) radiation properties from high-Tc superconductor thin film log-periodic antennas. Three sets of wire grid polarizers are employed to characterize the frequency-dependent polarization of the THz beam. The polarized radiation has clear resonance at frequencies corresponding to the antenna structures. The polarization patterns are thus well explained by the antenna structures. © 2001 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0921-4534(01)00696-7

Time-domain terahertz spectroscopy of (100)(LaAlO<inf>3</inf>)<inf>0.3</inf>-(Sr<inf>2</inf> AlTaO<inf>6</inf>)<inf>0.7</inf> substrate

Toshihiko Kiwa, Masayoshi Tonouchi

Japanese Journal of Applied Physics, Part 2: Letters 40 ( 1 A/B ) L38 - L40 2001.1

Language：English Publisher：INST PURE APPLIED PHYSICS

We measured terahertz (THz) properties of high-Tc superconductor's (HTS's) substrates, (100) MgO and (100) (LaAlO3)0.3-(Sr2 AlTaO6)0.7 (LSAT), at frequencies between 0.5 THz and 2 THz using time-domain terahertz spectroscopy (TDTS). The complex refractive index ñ and dielectric function ε̃ of the MgO substrate were independent of frequencies; those of LSAT slightly increased with increasing frequency. It was determined that ñ = 3.17 + i0.004 and ε̃ = 10.1 + i0.06 for the MgO substrate and ñ = 4.8 + i0.02 and ε̃ = 24 + i0.2 for the LSAT substrate at 1 THz. The LSAT values were almost independent of the temperature at these frequencies. The dielectric loss tan δ's of the LSAT and the MgO substrates were less than 0.01. The tan δ's of LSAT were several times larger than those of MgO, and increased with an increase of frequency.

DOI： 10.1143/jjap.40.l38

Tl₂Ba₂CaCu₂O_8+δからの光励起ジョセフソンプラズマ放射

富成征弘, 紀和利彦, 村上博成, 斗内政吉, WALD H, SEIDEL P, SCHNEIDEWIND H

光物性研究会論文集 12th 2001

Femtosecond optical response of Y dopping Bi2212 single crystal.

富成征弘, 紀和利彦, 村上博成, 斗内政吉, 荒井毅, 青峰隆文

電子情報通信学会技術研究報告 101 ( 183(SCE2001 16-23) ) 2001

ポンププローブテラヘルツ電磁波励起による光励起電荷ダイナミックスの評価(II)LT-GaAsの場合

河崎尚寛, 吉村尚洋, 紀和利彦, 村上博成, 斗内政吉

応用物理学関係連合講演会講演予稿集 48th ( 3 ) 2001

非晶質半導体薄膜のフェムト秒光応答とテラヘルツ電磁波放射

紀和利彦, 河崎尚寛, 吉村尚洋, 村上博成, 斗内政吉

応用物理学関係連合講演会講演予稿集 48th ( 2 ) 2001

BSCCO薄膜の時間領域テラヘルツ分光

村上博成, 紀和利彦, 斗内政吉, 斗内政吉, 内山哲治, 内山哲治, 井口家成, 井口家成

応用物理学関係連合講演会講演予稿集 48th ( 1 ) 2001

La_0.7Sr_0.3MnO_3-δ薄膜の作製とフェムト秒時間領域反射率変化

小谷研太, 紀和利彦, 貴田徳明, 村上博成, 斗内政吉

応用物理学関係連合講演会講演予稿集 48th ( 1 ) 2001

Bi₂Sr₂Ca_0.8Y_0.2CuO_8+δ単結晶の作製とフェムト秒光パルス応答

富成征弘, 荒井毅, 青峰隆文, 紀和利彦, 村上博成, 斗内政吉

応用物理学関係連合講演会講演予稿集 48th ( 1 ) 2001

Optical response in amorphous GaAs thin films prepared by pulsed laser deposition

Toshihiko Kiwa, Ichiro Kawashima, Shigeki Nashima, Masanori Hangyo, Masayoshi Tonouchi

Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers 39 ( 11 ) 6304 - 6308 2000.11

Language：English Publisher：INST PURE APPLIED PHYSICS

Femtosecond optical response in GaAs thin films has been studied. We prepared GaAs thin films on MgO substrates and on YBa2Cu3O7-δ (YBCO) thin films using pulsed laser deposition (PLD) at temperatures below 250 °C. A photocarrier lifetime of less than 1 ps is measured for the prepared GaAs thin films using femtosecond time-domain reflectivity change measurements. Pulsed electromagnetic wave [terahertz (THz) radiation] containing a frequency component of up to 1 THz is emitted from fabricated photoconductive switches using the prepared thin films. We also evaluated the THz radiation properties emitted from the photoswitches on the YBCO thin films.

DOI： 10.1143/jjap.39.6304