研究者詳細 - 原　秀明

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Measurement of cesium 8 PJ2→6 PJ′2 electric quadrupole transition probabilities using fluorescence spectroscopy

Jing Wang, Yuki Miyamoto, Hideaki Hara, Minoru Tanaka, Motomichi Tashiro, Noboru Sasao

Physical Review A 2024年7月

Periodic superradiance in an Er:YSO crystal 査読

Hideaki Hara, Junseok Han, Yasutaka Imai, Noboru Sasao, Akihiro Yoshimi, Koji Yoshimura, Motohiko Yoshimura, Yuki Miyamoto

Physical Review Research 2024年1月

Parity violating magnetization at neutrino pair emission using trivalent lanthanoid ions 査読

Hideaki Hara, Akihiro Yoshimi, Motohiko Yoshimura

Physical Review D 104 ( 11 ) 2021年12月

Simulation Study of Laser Ionization of Muonium by 1S-2S Excitation for the Muon g − 2/EDM Experiment at J-PARC

Ce Zhang, Hideaki Hara, Takahiro Hiraki, Yutaka Ikedo, Yasutaka Imai, Katsuhiko Ishida, Saeid Kamal, Naritoshi Kawamura, Akihiro Koda, Yajun Mao, Takahiko Masuda, Tsutomu Mibe, Yasuhiro Miyake, Yuki Miyamoto, Yu Oishi, Masashi Otani, Patrick Strasser, Koichiro Shimomura, Kazuhito Suzuki, Satoshi Uetake, Takayuki Yamazaki, Shinsuke Yamamoto, Koji Yoshimura, Mitsuhiro Yoshida

Proceedings of the 3rd J-PARC Symposium (J-PARC2019) 2021年3月

Geometry-dependent spectra and coherent-transient measurement of nearly degenerate four-wave mixing using two-photon resonance 査読

Hideaki Hara, Yuki Miyamoto, Takahiro Hiraki, Kei Imamura, Takahiko Masuda, Noboru Sasao, Satoshi Uetake, Akihiro Yoshimi, Koji Yoshimura, Motohiko Yoshimura

Journal of Physics B: Atomic, Molecular and Optical Physics 52 ( 23 ) 235402 2019年12月

Neutrino mass spectroscopy using Er3+ ions placed at inversion center of host crystals

H. Hara, N. Sasao, A. Yoshimi, M. Yoshimura

arXiv:1910.14318v1 2019年10月

X-ray pumping of the 229Th nuclear clock isomer 査読

Takahiko Masuda, Akihiro Yoshimi, Akira Fujieda, Hiroyuki Fujimoto, Hiromitsu Haba, Hideaki Hara, Takahiro Hiraki, Hiroyuki Kaino, Yoshitaka Kasamatsu, Shinji Kitao, Kenji Konashi, Yuki Miyamoto, Koichi Okai, Sho Okubo, Noboru Sasao, Makoto Seto, Thorsten Schumm, Yudai Shigekawa, Kenta Suzuki, Simon Stellmer, Kenji Tamasaku, Satoshi Uetake, Makoto Watanabe, Tsukasa Watanabe, Yuki Yasuda, Atsushi Yamaguchi, Yoshitaka Yoda, Takuya Yokokita, Motohiko Yoshimura, Koji Yoshimura

Nature 573 ( 7773 ) 238 - 242 2019年9月

Raman stimulated neutrino pair emission 査読

Hideaki Hara, Motohiko Yoshimura

The European Physical Journal C 79 ( 8 ) 2019年8月

Coherent two-photon emission from hydrogen molecules excited by counter-propagating laser pulses 査読

Takahiro Hiraki, Hideaki Hara, Yuki Miyamoto, Kei Imamura, Takahiko Masuda, Noboru Sasao, Satoshi Uetake, Akihiro Yoshimi, Koji Yoshimura, Motohiko Yoshimura

Journal of Physics B: Atomic, Molecular and Optical Physics 52 ( 4 ) 045401 - 045401 2019年2月

Nuclear resonant scattering experiment with fast time response: Photonuclear excitation of Hg 201 査読

A. Yoshimi, H. Hara, T. Hiraki, Y. Kasamatsu, S. Kitao, Y. Kobayashi, K. Konashi, R. Masuda, T. Masuda, Y. Miyamoto, K. Okai, S. Okubo, R. Ozaki, N. Sasao, O. Sato, M. Seto, T. Schumm, Y. Shigekawa, S. Stellmer, K. Suzuki, S. Uetake, M. Watanabe, A. Yamaguchi, Y. Yasuda, Y. Yoda, K. Yoshimura, M. Yoshimura

Physical Review C 97 ( 2 ) 2018年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：American Physical Society

Nuclear resonant excitation and detection of its decay signal for the 26.27-keV level of Hg201 is demonstrated with high-brilliance synchrotron radiation (SR) and a fast x-ray detector system. This SR-based photonuclear excitation scheme, known as nuclear resonant scattering (NRS) in the field of materials science, is also useful for investigating nuclear properties, such as the half-lives and radiative widths of excited nuclear levels. To date, because of the limited time response of the x-ray detector, the nuclear levels to which this method could be applied have been limited to the one whose half-lives are longer than ∼1 ns. The faster time response of the NRS measurement makes possible NRS experiments on nuclear levels with much shorter half-lives. We have fabricated an x-ray detector system that has a time resolution of 56 ps and a shorter tail function than that reported previously. With the implemented detector system, the NRS signal of the 26.27-keV state of Hg201 could be clearly discriminated from the electronic scattering signal at an elapsed time of 1 ns after the SR pulse. The half-life of the state was determined as 629 ± 18 ps, which has better precision by a factor of three compared with that reported to date obtained from nuclear decay spectroscopy.

DOI： 10.1103/PhysRevC.97.024607

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Vibrational excitation of hydrogen molecules by two-photon absorption and third-harmonic generation 査読

Yuki Miyamoto, Hideaki Hara, Takahiro Hiraki, Takahiko Masuda, Noboru Sasao, Satoshi Uetake, Akihiro Yoshimi, Koji Yoshimura, Motohiko Yoshimura

JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS 51 ( 1 ) 2018年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：IOP PUBLISHING LTD

We report the coherent excitation of the vibrational state of hydrogen molecules by two-photon absorption and the resultant third-harmonic generation (THG). Parahydrogen molecules cooled by liquid nitrogen are irradiated by mid-infrared nanosecond pulses at 4.8 mu m with a nearly Fourier-transform-limited linewidth. The first excited vibrational state of parahydrogen is populated by two-photon absorption of the mid-infrared photons. Because of the narrow linewidth of the mid-infrared pulses, coherence between the ground and excited states is sufficient to induce higher-order processes. Near-infrared photons from the THG are observed at 1.6 mu m. The dependence of the intensity of the near-infrared radiation on mid-infrared pulse energy, target pressure, and cell length is determined. We used a simple formula for THG with consideration of realistic experimental conditions to explain the observed results.

DOI： 10.1088/1361-6455/aa9782

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Frequency dependence of coherently amplified two-photon emission from hydrogen molecules 査読

Hideaki Hara, Yuki Miyamoto, Takahiro Hiraki, Takahiko Masuda, Noboru Sasao, Satoshi Uetake, Akihiro Yoshimi, Koji Yoshimura, Motohiko Yoshimura

PHYSICAL REVIEW A 96 ( 6 ) 2017年12月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER PHYSICAL SOC

We investigate how the efficiency of coherently amplified two-photon emission depends on the frequency of one of the two emitted photons, namely the signal photon. This is done over the wavelength range of 5.048-10.21 mu m by using the vibrational transition of parahydrogen. The efficiency increases with the frequency of the signal photon. Considering experimental errors, our results are consistent with the theoretical prediction for the present experimental conditions. This study is an experimental demonstration of the frequency dependence of coherently amplified two-photon emission, and also presents its potential as a light source.

DOI： 10.1103/PhysRevA.96.063827

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Fast x-ray detector system with simultaneous measurement of timing and energy for a single photon 査読

T. Masuda, S. Okubo, H. Hara, T. Hiraki, S. Kitao, Y. Miyamoto, K. Okai, R. Ozaki, N. Sasao, M. Seto, S. Uetake, A. Yamaguchi, Y. Yoda, A. Yoshimi, K. Yoshimura

REVIEW OF SCIENTIFIC INSTRUMENTS 88 ( 6 ) 2017年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER INST PHYSICS

We developed a fast X-ray detector system for nuclear resonant scattering (NRS) experiments. Our system employs silicon avalanche photo-diode (Si-APD) as a fast X-ray sensor. The system is able to acquire both timing and energy of a single X-ray photon simultaneously in a high rate condition, 106 counts per second for one Si-APD. The performance of the system was investigated in SPring-8, a synchrotron radiation facility in Japan. Good time resolution of 120 ps (FWHM) was achieved with a slight tail distribution in the time spectrum by a level of 10(-9) at 1 ns apart from the peak. Using this system, we successfully observed the NRS from the 26.27-keV level of mercury-201, which has a half-life of 630(50) ps. We also demonstrated the reduction of background events caused by radioactive decays in a radioactive sample by discriminating photon energy. Published by AIP Publishing.

DOI： 10.1063/1.4989405

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Vibrational Two-Photon Emission from Coherently Excited Solid Parahydrogen 査読

Yuki Miyamoto, Hideaki Hara, Takahiko Masuda, Noboru Sasao, Satoshi Uetake, Akihiro Yoshimi, Koji Yoshimura, Motohiko Yoshimura

JOURNAL OF PHYSICAL CHEMISTRY A 121 ( 20 ) 3943 - 3951 2017年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER CHEMICAL SOC

We report the observation of two-photon emission from a coherently excited vibrational state of solid parahydrogen, which is also a known quantum solid. Coherence between the ground and the excited states is prepared by stimulated Raman scattering using two visible laser pulses. The two-photon emission is triggered by another mid-infrared laser pulse. It was observed that the two-photon emission persists even when the trigger pulse is injected long after the excitation. This is due to the long decoherence time of the vibrational states of solid parahydrogen. It is found that the emission intensity increases even after the excitation pulses pass through the target completely. This coherence development is highly suppressed at high target temperatures and high residual orthohydrogen concentrations. Effects of target annealing and laser-induced damage on the target are also observed.

DOI： 10.1021/acs.jpca.7b02011

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Injection-seeded tunable mid-infrared pulses generated by difference frequency mixing 査読

Yuki Miyamoto, Hideaki Hara, Takahiko Masuda, Takahiro Hiraki, Noboru Sasao, Satoshi Uetake

JAPANESE JOURNAL OF APPLIED PHYSICS 56 ( 3 ) 2017年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：IOP PUBLISHING LTD

We report on the generation of nanosecond mid-infrared pulses having frequency tunability, a narrow linewidth, and a high pulse energy. These pulses are obtained by frequency mixing between injection-seeded near-infrared pulses in potassium titanyl arsenate crystals. A continuous-wave external cavity laser diode or a Ti:sapphire ring laser is used as a tunable seeding source for the near-infrared pulses. The typical energy of the generated mid-infrared pulses is in the range of 0.4-1mJ/pulse. The tuning wavelength ranges from 3142 to 4806 nm. A narrow linewidth of 1.4GHz and good frequency reproducibility of the mid-infrared pulses are confirmed by observing a rovibrational absorption line of gaseous carbon monoxide at 4587 nm. (C) 2017 The Japan Society of Applied Physics

DOI： 10.7567/JJAP.56.032101

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Recent progress of SPAN towards neutrino mass spectroscopy 査読

Masuda T, Hara H, Miyamoto Y, Sasao N, Tanaka M, Uetake S, Yoshimi A, Yoshimura K, Yoshimura M

Journal of Physics: Conference Series 718 ( 6 ) 2016年

Rate amplification of the two photon emission from para-hydrogen toward the neutrino mass measurement 査読

Takahiko Masuda, Hideaki Hara, Yuki Miyamoto, Susumu Kuma, Itsuo Nakano, Chiaki Ohae, Noboru Sasao, Minoru Tanaka, Satoshi Uetake, Akihiro Yoshimi, Koji Yoshimura, Motohiko Yoshimura

HYPERFINE INTERACTIONS 236 ( 1-3 ) 73 - 77 2015年11月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）出版者・発行元：SPRINGER

We recently reported an experiment which focused on demonstrating the macro-coherent amplification mechanism. This mechanism, which was proposed for neutrino mass measurements, indicates that a multi-particle emission rate should be amplified by coherence in a suitable medium. Using a para-hydrogen molecule gas target and the adiabatic Raman excitation method, we observed that the two photon emission rate was amplified by a factor of more than 10(15) from the spontaneous emission rate. This paper briefly summarizes the previous experimental result and presents the current status and the future prospect.

DOI： 10.1007/s10751-015-1177-1

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Externally triggered coherent two-photon emission from hydrogen molecules 査読

Yuki Miyamoto, Hideaki Hara, Takahiko Masuda, Noboru Sasao, Minoru Tanaka, Satoshi Uetake, Akihiro Yoshimi, Koji Yoshimura, Motohiko Yoshimura

PROGRESS OF THEORETICAL AND EXPERIMENTAL PHYSICS 2015 ( 8 ) 2015年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：OXFORD UNIV PRESS INC

We report on coherent enhancement of two-photon emission from the excited vibrational state of molecular hydrogen triggered by irradiating mid-infrared pulses externally. We previously observed the two-photon emission triggered by the internally generated fourth Stokes photons. By injecting independent mid-infrared pulses externally, it is possible to control the experimental parameters and investigate the mechanism in more detail. In this article, we describe the two-photon emission using the external trigger pulses. Its spectrum and dependence on the energy and timing of the trigger pulse are presented along with numerical simulations based on the Maxwell-Bloch equations. The measured number of emitted photons is 6 x 10(11) photons/pulse and the resulting enhancement factor from the spontaneous emission is more than 10(18). This value is three orders of magnitude higher than that of the previous experiment. External control of the emission process is expected to be essential for observation of the weaker process of radiative emission of a neutrino pair.

DOI： 10.1093/ptep/ptv103

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Observation of coherent two-photon emission from the first vibrationally excited state of hydrogen molecules 査読

Yuki Miyamoto, Hideaki Hara, Susumu Kuma, Takahiko Masuda, Itsuo Nakano, Chiaki Ohae, Noboru Sasao, Minoru Tanaka, Satoshi Uetake, Akihiro Yoshimi, Koji Yoshimura, Motohiko Yoshimura

PROGRESS OF THEORETICAL AND EXPERIMENTAL PHYSICS 2014 ( 11 ) 2014年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：OXFORD UNIV PRESS INC

In this paper, we describe an experiment which was conducted to explore the macro-coherent amplification mechanism using a two-photon emission process from the first vibrationally excited state of the para-hydrogen molecule. Large coherence in the initial state was prepared by the adiabatic Raman method, and the lowest Stokes sideband was used as a trigger field. We observed coherent two-photon emission consistent with the expectation of the Maxwell-Bloch equation derived for the process, whose rate is larger by many orders of magnitude than that of spontaneous emission.

DOI： 10.1093/ptep/ptu152

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A Three-Dimensional Optical Lattice of Ytterbium and Lithium Atomic Gas Mixture 査読

Hideaki Hara, Hideki Konishi, Shuta Nakajima, Yosuke Takasu, Yoshiro Takahashi

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 83 ( 1 ) 2014年1月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PHYSICAL SOC JAPAN

We develop an optical lattice system for an ultracold atomic gas mixture of ytterbium (Yb-174) and lithium (Li-6), which is an ideal system for studying disorder and impurity problems. We load a Bose-Einstein condensate of Yb-174 into a three-dimensional optical lattice and observe its interference patterns in time-of-flight (TOF) images. Furthermore, we perform laser spectroscopy of Yb-174 in an optical lattice using the ultranarrow optical transition S-1(0)-P-3(2) in both cases with and without Li-6. Owing to the weak interspecies interaction, we do not observe clear effects of Li-6 in the obtained interference patterns or excitation spectra. However, this is an important first step in the optical control of atomic impurity in ultracold fermions. We also measure the polarizabilities of the P-3(2) state of Yb-174 atoms in an optical trap with a wavelength of 1070 nm. We reveal that the polarizability can be tuned to be positive, zero, or the same as the ground state, which is useful for certain applications.

DOI： 10.7566/JPSJ.83.014003

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Photoassociative production of ultracold heteronuclear ytterbium molecules 査読

Mateusz Borkowski, Roman Ciurylo, Paul S. Julienne, Rekishu Yamazaki, Hideaki Hara, Katsunari Enomoto, Shintaro Taie, Seiji Sugawa, Yosuke Takasu, Yoshiro Takahashi

PHYSICAL REVIEW A 84 ( 3 ) 2011年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER PHYSICAL SOC

We report observations of photoassociation (PA) spectra near the intercombination line in isotopic mixtures of ultracold ytterbium gases. Several heteronuclear bound states have been found for the excited (170)Yb(174)Yb and (174)Yb(176)Yb molecules. We develop a single-channel mass-scaled interaction model for the excited state molecule which well reproduces the measured bound state energies. This is an important step toward optical control of interactions in mixtures of ultracold ytterbium gases using heteronuclear optical Feshbach resonances. The model developed is applicable in collisions of other similar systems, such as cadmium and mercury.

DOI： 10.1103/PhysRevA.84.030702

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Quantum Degenerate Mixtures of Alkali and Alkaline-Earth-Like Atoms 査読

Hideaki Hara, Yosuke Takasu, Yoshifumi Yamaoka, John M. Doyle, Yoshiro Takahashi

PHYSICAL REVIEW LETTERS 106 ( 20 ) 2011年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：AMER PHYSICAL SOC

We realize simultaneous quantum degeneracy in mixtures consisting of the alkali and alkaline earth like atoms Li and Yb. This is accomplished within an optical trap by sympathetic cooling of the fermionic isotope Li-6 with evaporatively cooled bosonic Yb-174 and, separately, fermionic Yb-173. Using cross-thermalization studies, we also measure the elastic s-wave scattering lengths of both Li-Yb combinations, vertical bar a(6Li-174Yb)vertical bar = 1.0 +/- 0.2 nmand vertical bar a(6Li-173Yb)vertical bar = 0.9 +/- 0.2 nm. The equality of these lengths is found to be consistent with massscaling analysis. The quantum degenerate mixtures of Li and Yb, as realized here, can be the basis for creation of ultracold molecules with electron spin degrees of freedom, studies of novel Efimov trimers, and impurity probes of superfluid systems.

DOI： 10.1103/PhysRevLett.106.205304

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Simultaneous magneto-optical trapping of lithium and ytterbium atoms towards production of ultracold polar molecules 査読

M. Okano, H. Hara, M. Muramatsu, K. Doi, S. Uetake, Y. Takasu, Y. Takahashi

APPLIED PHYSICS B-LASERS AND OPTICS 98 ( 4 ) 691 - 696 2010年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：SPRINGER

We have successfully implemented the first simultaneous magneto-optical trapping (MOT) of lithium ((6)Li) and ytterbium ((174)Yb) atoms towards production of ultracold polar molecules of LiYb. For this purpose, we developed the dual atomic oven which contains both atomic species as an atom source and successfully observed the spectra of the Li and Yb atoms in the atomic beams from the dual atomic oven. We constructed the vacuum chamber including the glass cell with the windows made of zinc selenium (ZnSe) for the CO(2) lasers, which are the useful light sources of optical trapping for evaporative and sympathetic cooling. Typical atom numbers and temperatures in the compressed MOT are 7x10(3) atoms, 640 mu K for (6)Li, 7x10(4) atoms, and 60 mu K for (174)Yb, respectively.

DOI： 10.1007/s00340-009-3728-0

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