Faculty Profiles - YOKOYA Takayoshi

Papers - YOKOYA Takayoshi

Division display 1 - 20 of about 317 ／ All the affair displays >>

Local-structure insight into the improved superconducting properties of Pb-substituted La(O, F)BiS2: a photoelectron holography study

YaJun Li, Yusuke Hashimoto, Noriyuki Kataoka, Zexu Sun, Sota Kawamura, Hiroto Tomita, Taro Setoguchi, Soichiro Takeuchi, Shunjo Koga, Kohei Yamagami, Yoshinori Kotani, Satoshi Demura, Kanako Noguchi, Hideaki Sakata, Tomohiro Matsushita, Takanori Wakita, Yuji Muraoka, Takayoshi Yokoya

Scientific Reports 15 ( 1 ) 2025.3

Publishing type：Research paper (scientific journal) Publisher：Springer Science and Business Media LLC

Abstract

Pb-substituted La(O, F)BiS₂ (Pb-LaOFBiS₂) exhibits improved superconducting properties and a resistivity anomaly around 100 K that is attributed to a structural transition. We have performed temperature(T)-dependent photoelectron holography (PEH) to study dopant incorporation sites and the local structure change across the anomaly. The PEH study of Pb-LaOFBiS₂ provided evidence for the dominant incorporation sites of Pb and F: Pb atoms are incorporated into the Bi sites and F atoms are incorporated into the O site. No remarkable difference in the local structures around Pb and Bi atoms was observed. Across the temperature of the resistivity anomaly (T ^*), photoelectron holograms of Bi 4f changed. Comparisons of holograms with those of non-substituted LaOFBiS₂ sample, as well as simulated holograms, suggested that (1), above T ^*, the tetragonal structure of Pb-LaOFBiS₂ is different from the tetragonal structure of LaOFBiS₂ and (2), below T ^*, the tetragonal structure still remains in Pb-LaOFBiS₂. We discuss a possible origin of the difference in the structure above T ^* and the implication of the result below T ^*, which are necessary ingredients to understand the physical properties of Pb-LaOFBiS₂.

DOI： 10.1038/s41598-025-86233-2

researchmap

Other Link： https://www.nature.com/articles/s41598-025-86233-2

Effects of thermal energy on the formation of lattice strain in VO2 thin films grown on TiO2(001) Reviewed

Reki Nakamoto, Hiroyuki Okazaki, Takanori Wakita, Takayoshi Yokoya, Yuji Muraoka

Langmuir 40 ( 46 ) 24447 - 24454 2024.11

First-principles calculations concerning ferromagnetism in Q-carbon Reviewed

Qiang Yue, Takayoshi Yokoya, Yuji Muraoka

Diamond and Related Materials 111807 - 111807 2024.11

Structural and Superconducting Properties of Bi₂Rh₃(Se_1–xS_x)₂ (x = 0–1.0) Reviewed

Zhiyan Zhang, Wanli Pan, Masaki Utsumi, Yuki Yamamoto, Hidenori Goto, Ryusuke Kondo, Takayoshi Yokoya, Ryota Goban, Tomoki Higashikawa, Ritsuko Eguchi, Yasuhiro Takabayashi, Koichi Hayashi, Hirofumi Ishii, Tatsuo C. Kobayashi, Yoshihiro Kubozono

Inorganic Chemistry 63 ( 45 ) 21531 - 21540 2024.10

First-principles molecular dynamics simulations for the properties of boron-doped tetrahedral amorphous carbon Reviewed

Qiang Yue, Takayoshi Yokoya, Yuji Muraoka

Diamond and Related Materials 143 110894 2024.2

Molecular dynamics simulation of deposition of amorphous carbon films on sapphire surfaces Reviewed

Qiang Yue, Takayoshi Yokoya, Yuji Muraoka

Diamond and Related Materials 140 110514 - 110514 2023.12

Photoelectron holographic evidence for the incorporation site of Se and suppressed atomic displacement of the conducting layer of La(O,F)BiSSe Reviewed

YaJun Li, ZeXu Sun, Noriyuki Kataoka, Taro Setoguchi, Yusuke Hashimoto, Soichiro Takeuchi, Shunjo Koga, Kazuhisa Hoshi, Yoshikazu Mizuguchi, Tomohiro Matsushita, Takanori Wakita, Yuji Muraoka, Takayoshi Yokoya

Japanese Journal of Applied Physics 62 ( 12 ) 125001 - 125001 2023.11

Authorship：Corresponding author Publishing type：Research paper (scientific journal) Publisher：IOP Publishing

Abstract

La(O,F)BiS_2-xSe_x is a layered material that is considered to be a candidate exotic superconductor as well as a promising thermoelectrical material. We performed soft X-ray photoelectron holography to study the Se incorporation site and the local atomic arrangement of the conducting layer. A comparison of the experimental holograms with the simulated holograms indicates that Se atoms preferentially occupy the S sites in the conducting Bi–S plane of La(O,F)BiS₂. A comparison between the state-of-the-art holographic reconstructions of La(O,F)BiSSe and La(O,F)BiS₂ suggests that Se substitution suppresses the displacement of S atoms in La(O,F)BiS₂. These results provide photoelectron holographic evidence for the Se incorporation site and the Se-induced suppression of in-plane disorder.

DOI： 10.35848/1347-4065/ad079b

researchmap

Other Link： https://iopscience.iop.org/article/10.35848/1347-4065/ad079b/pdf

Controlling of Localization by Elemental-substitution Effect in Layered BiCh₂-based Compounds LaO₁₋_xF_xBiS₂₋_ySe_y Reviewed

Kazuhisa Hoshi, Hiroto Arima, Noriyuki Kataoka, Masayuki Ochi, Aichi Yamashita, Anne de Visser, Takayoshi Yokoya, Kazuhiko Kuroki, Yoshikazu Mizuguchi

Journal of the Physical Society of Japan 92 ( 5 ) 2023.5

Photoelectron Holography Study of La(O,F)BiS₂ Reviewed

YaJun Li, ZeXu Sun, Noriyuki Kataoka, Taro Setoguchi, Yusuke Hashimoto, Soichiro Takeuchi, Shunjo Koga, Satoshi Demura, Kanako Noguchi, Hideaki Sakata, Yoshikazu Mizuguchi, Tomohiro Matsushita, Takanori Wakita, Yuji Muraoka, Takayoshi Yokoya

Journal of the Physical Society of Japan 92 ( 4 ) 2023.4

Synthesis and Characterization of a Trigonal Layered Compound AgInS₂ Reviewed

Takahiro Sawahara, Ryo Matsumoto, Yuki Nakahira, Hidetomo Usui, Noriyuki Kataoka, Ryusei Saitou, Takanori Wakita, Takayoshi Yokoya, Aichi Yamashita, Yosuke Goto, Yoshihiko Takano, Akira Miura, Yoshikazu Mizuguchi

ACS Omega 8 ( 12 ) 11288 - 11292 2023.3

Self-organized vertical multilayer structures in spinodally decomposed TiO2-VO2 films on glass substrates Reviewed

Yuji Muraoka, Kazutada Takeda, Yoshito Takemoto, Takanori Wakita, Takayoshi Yokoya

Thin Solid Films 769 139749 - 139749 2023.3

Temperature dependent local inhomogeneity and magnetic moments of (Li_1−xFe_x)OHFeSe superconductors Reviewed

G. Tomassucci, L. Tortora, G. M. Pugliese, F. Stramaglia, L. Simonelli, C. Marini, K. Terashima, T. Wakita, S. Ayukawa, T. Yokoya, K. Kudo, M. Nohara, T. Mizokawa, N. L. Saini

Physical Chemistry Chemical Physics 2023

Photoelectron Diffraction and Holography Studies on Dopant Local Structures Invited Reviewed

Takayoshi Yokoya

Journal of the Physical Society of Japan 91 ( 9 ) 2022.9

Modification of the synthesis of layered titanium chloride nitride Reviewed

Masashi Tanaka, Noriyuki Kataoka, Haruya Kobayashi, Masaya Fujioka, Masaru Oda, Aishi Yamamoto, Kensei Terashima, Junji Nishii, Hiromi Tanaka, Takayoshi Yokoya

Materials Research Bulletin 153 111896 - 111896 2022.9

Anomalously large spin-dependent electron correlation in the nearly half-metallic ferromagnet <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>CoS</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math> Reviewed

Hirokazu Fujiwara, Kensei Terashima, Junya Otsuki, Nayuta Takemori, Harald O. Jeschke, Takanori Wakita, Yuko Yano, Wataru Hosoda, Noriyuki Kataoka, Atsushi Teruya, Masashi Kakihana, Masato Hedo, Takao Nakama, Yoshichika Ōnuki, Koichiro Yaji, Ayumi Harasawa, Kenta Kuroda, Shik Shin, Koji Horiba, Hiroshi Kumigashira, Yuji Muraoka, Takayoshi Yokoya

Physical Review B 106 ( 8 ) 2022.8

Superconductivity in the α-Form Layer Structured Metal Nitride Halide Reviewed

Masashi Tanaka, Noriyuki Kataoka, Takayoshi Yokoya

Condensed Matter 7 ( 2 ) 33 - 33 2022.4

Publishing type：Research paper (scientific journal) Publisher：MDPI AG

Layered metal nitride halides MNX (M = Ti, Zr, Hf; X = Cl, Br, I) have two polymorphs, including α- and β-forms, which have the FeOCl and SmSI structures, respectively. These compounds are band insulators and become metals and show superconductivity after electron doping by intercalating alkali metals between the layers. The superconductivity of β-form had been extensively characterized from decades ago, but it is not easy to consistently interpret all experimental results using conventional phonon-mediated Bardeen–Cooper–Schriefer mechanisms. The titanium compound TiNCl crystallizes only in the α-form structure. TiNCl also exhibits superconductivity as high as ~16 K after electron doping by intercalating metals and/or organic basis. It is important to compare the superconductivity of different M–N networks. However, α-form compounds are vulnerable to moisture, unlike β-form ones. The intercalation compounds are even more sensitive to humid air. Thus, there are few experimental studies on the superconducting mechanism of α-form, although it has been discussed for exotic Cooper-pairing mechanisms. This short review gathers the recent progress in experimental studies of TiNCl.

DOI： 10.3390/condmat7020033

researchmap

Incorporation Site and Valence State of Sn Atoms in Sn-Substituted La(O,F)BiS2 Superconductor Reviewed

YaJun Li, ZeXu Sun, Noriyuki Kataoka, Taro Setoguchi, Yusuke Hashimoto, Soichiro Takeuchi, Shunjo Koga, Takayuki Muro, Satoshi Demura, Kanako Noguchi, Hideaki Sakata, Tomohiro Matsushita, Ikuto Kawasaki, Shin-ichi Fujimori, Takanori Wakita, Yuji Muraoka, Takayoshi Yokoya

J. Phys. Soc. Jpn. 91 ( 5 ) 054602 2022.4

Strain relaxation and spinodal decomposition in composition adjusted TiO2-VO2 films on TiO2(100) substrates Reviewed

Takahiro Fukuda, Yoshito Takemoto, Takanori Wakita, Takayoshi Yokoya, Yuji Muraoka

Thin Solid Films 751 139210 2022.4

The Local Structure of the BiS2 Layer in RE(O,F)BiS2 Determined by In-Plane Polarized X-ray Absorption Measurements Reviewed

G. M. Pugliese, L. Tortora, E. Paris, T. Wakita, K. Terashima, A. Puri, M. Nagao, R. Higashinaka, T. D. Matsuda, Y. Aoki, T. Yokoya, T. Mizokawa, N. L. Saini

Physchem 1 ( 3 ) 250 - 258 2021.11

Publishing type：Research paper (scientific journal) Publisher：MDPI AG

We have investigated the local structure of BiS2-based layered materials by Bi L3-edge extended X-ray absorption fine structure (EXAFS) measurements performed on single crystal samples with polarization of the X-ray beam parallel to the BiS2 plane. The results confirm highly instable nature of BiS2 layer, characterized by ferroelectric like distortions. The distortion amplitude, determined by the separation between the two in-plane (Bi-S1) bonds, is found to be highest in LaO0.77F0.23BiS2 with ΔR∼0.26 Å and lowest in NdO0.71F0.29BiS2 with ΔR∼0.13 Å. Among the systems with intrinsic doping, CeOBiS2 shows smaller distortion (ΔR∼0.15 Å) than PrOBiS2 (ΔR∼0.18 Å) while the highest distortion appears for EuFBiS2 revealing ΔR∼0.22 Å. It appears that the distortion amplitude is controlled by the nature of the RE(O,F) spacer layer in the RE(O,F)BiS2 structure. The X-ray absorption near edge structure (XANES) spectra, probing the local geometry, shows a spectral weight transfer that evolves systematically with the distortion amplitude in the BiS2-layer. The results provide a quantitative measurements of the local distortions in the instable BiS2-layer with direct implication on the physical properties of these materials.

DOI： 10.3390/physchem1030019

researchmap

Photoinduced oxygen transport in cobalt double-perovskite crystal EuBaCo2O5.39 Reviewed

M. Hada, O. S. Ohmura, T. Ishikawa, M. Saigo, N. Keio, W. Yajima, T. Suzuku, D. Urushihara, K. Takubo, Y. Masaki, M. Kuwahara, K. Tsuruta, Y. Hayashi, J. Matsuno, T. Yokooya, K. Onda, F. Shimojo, M. Mase, S. Ishihara, T. Asaka, N. Abe

Applied Materials Today 24 101167 - 101167 2021.9

　 PREV - NEXT 　

< YOKOYA Takayoshi >

Papers - YOKOYA Takayoshi