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Huang, Y.-C.*; 吉川 貴史; 他5名*
Applied Physics Letters, 126(9), p.092403_1 - 092403_6, 2025/03
被引用回数：0 パーセンタイル：0.00(Physics, Applied)The application of spin-current volume effect (SVE) with volume magnetostriction of iron gallium (FeGa) films is examined for micro-diaphragm actuation. A silicon diaphragm measuring 1.5
1.5 mm
is coated with Pt (100-nm-thick) and FeGa (100-nm-thick) thin films. An alternating charge current passed through the FeGa/Pt/Si diaphragm under a magnetic field perpendicular to the charge current generates an alternating spin current via the spin Hall effect in the Pt film, transferring angular momentum from the Pt film to the FeGa film. The injected spin current provides energy and changes the effective temperature, thereby varying the thermal fluctuation of the magnetic moments. In a magnetic material with volume magnetostriction, the thermal fluctuation of the magnetic moments affects its volume. When the spin fluctuations change, the volume magnetostriction induces a corresponding expansion or contraction of the material. Both electrodeposited and ion-beam sputter-deposited FeGa films are investigated, and it is observed that the FeGa film exhibits SVE. The force generated by the SVE is evaluated based on the vibration amplitude at the fundamental resonant mode. This study demonstrates that the force generated by the SVE is correlated with the volume magnetostriction and the deposition process.
鈴木 誠也; 勝部 大樹*; 矢野 雅大; 津田 泰孝; 寺澤 知潮; 小澤 孝拓*; 福谷 克之; Kim, Y.*; 朝岡 秀人; 柚原 淳司*; et al.
Small Methods, 9(3), p.2400863_1 - 2400863_9, 2025/03
被引用回数：1 パーセンタイル：30.18(Chemistry, Physical)For group 14 monoelemental two-dimensional materials, such as silicene, germanene, and stanene, oxidation is a severe problem that alters or degrades their physical properties. This study shows that the oxidized germanene on Ag(111)/Ge(111) can be reformed to germanene by simple heating around 500 
C in a vacuum. The key reaction in reforming germanene is the desorption of GeO and GeO
during heating around 350 C. After removing surface oxygen, Ge further segregates to the surface, resulting in germanene. The reformed germanene has the same crystal structure, a (7
7) R19.1 supercell with respect to Ag(111), and has equivalent high quality to that of as-grown germanene on Ag(111)/Ge(111). Even after air oxidation, germanene can be reformed by annealing in a vacuum. On the other hand, the desorption of GeO and GeO at high temperatures was not suppressed even in the O backfilling atmosphere. This instability of oxidized germanene/Ag(111)/Ge(111) at high temperatures contributes to the ease of germanene reformation without oxygen. In other words, the present germanene reformation, as well as the segregation of germanene on Ag(111)/Ge(111), is a highly robust process as a synthesis method of germanene.
Moon, J. Y.*; 伊藤 由太; 他13名*
Journal of the Korean Physical Society, 9 Pages, 2024/12
被引用回数：0 パーセンタイル：0.00(Physics, Multidisciplinary)A new large-scale heavy-ion accelerator complex, RAON (Rare isotope Accelerator complex for ON-line experiments), in Korea has implemented the state-of-art device, multi-reflection time-of-flight mass spectrometer (MRTOF-MS) for the mass spectrometry of the exotic nuclei. Using the multi-reflections of ions between a pair of grid-free mirror electrodes and therefore extending the fly length, it can achieve the incredibly high mass resolving power of within a short measurement time of 
10 ms, providing the nuclear mass of the exotic nuclei with a high-precision level of sub-ppm. The device is coupled to one of the beamlines in the ISOL experimental hall, ready for participating in the longstanding topics of nuclear structure in the outskirts of the nuclear chart and nucleosynthesis of heavy elements in explosive astrophysical environments. The exclusively high mass resolving power is also advantageous for reducing the isobaric contaminants that rare isotope ion beam facilities suffer from. In this paper, we present a summary of the construction and current performance of the RAON MRTOF-MS.
Cf fission fragments with MRTOF-MS and detailed study of masses of neutron-rich Ce isotopes木村 創大*; 伊藤 由太; 他8名*
Physical Review C, 110(4), p.045810_1 - 045810_9, 2024/10
被引用回数：2 パーセンタイル：74.11(Physics, Nuclear)We report the mass measurements of neutron-rich isotopes produced via spontaneous fission of Cf using a multireflection time-of-flight mass spectrograph. The mass of 
Ce is determined experimentally for the first time. A discrepancy between the experimental and literature values was found for the mass of 
Sb, which was previously deduced through indirect measurements. In comparison with several theoretical predictions, both the values and the trend of the mass excesses of 
Ce cannot be consistently explained. The wide-range and simultaneous mass measurements of the multireflection time-of-flight mass spectrograph enable us to crosscheck the existing mass data, and the conflict between the measured time-of-flight ratio and the extracted mass would imply the necessity of re-examining them.
勅使河原 誠; 池田 裕二郎*; 村松 一生*; 須谷 康一*; 福住 正文*; 能田 洋平*; 小泉 智*; 猿田 晃一; 大竹 淑恵*
Journal of Neutron Research, 26(2-3), p.69 - 74, 2024/09
冷中性子のような低速中性子は、基礎物理学だけでなく、生命科学における構造ゲノミクスの進歩や水素社会への移行に必要な電池技術の進歩にとっても重要な非破壊プローブである。中性子を利用した科学は、中性子高強度依存科学とも呼ばれる。このエネルギー領域の中性子強度を増加させるため、ナノサイズ粒子群に着目した新しいユニークな方法が提案されている。この方法は、ナノサイズ粒子群による多重干渉性散乱による強度増強に基づく。ナノサイズ粒子群は、冷中性子以下の波長と一致することから、いわゆるブラッグ散乱と呼ばれる干渉性散乱と同様の効果を引き起こし、数桁もの中性子強度増強につながる。ナノダイヤモンドと水素化マグネシウムがこれまで数値的及び実験的に研究されているが、実用化において、ナノダイヤモンドの主な課題は賦形である。この問題の解決策を見出すために、我々は、もう一つの炭素構造体であるグラフェンに着目した。本論文では、冷中性子下の反射体材料としてのナノサイズグラフェンの可能性について、実験結果とともに報告する。
Fe
O
/Pt bilayer diskEmdi, G.*; 日置 友智*; 巻内 崇彦*; 齊藤 英治
Physical Review Applied (Internet), 22(3), p.L031002_1 - L031002_6, 2024/09
被引用回数：0 パーセンタイル：0.00(Physics, Applied)Sigmoidal curve behavior of 0 and n state probability in a magnon parametron, using yttrium iron garnet (YFeO) thin disk, is systematically investigated. We demonstrate that the probability distribution can be tuned by bias and pump microwave power. Our numerical calculation that considers increasing damping due to four-magnon scattering processes reproduces the results well.
C
reaction at 1.8 GeV/
with the Superconducting Kaon spectrometer市川 裕大; 藤田 真奈美; 長谷川 勝一; 今井 憲一*; 七村 拓野; 成木 恵; 佐藤 進; 佐甲 博之; 田村 裕和; 谷田 聖; et al.
Progress of Theoretical and Experimental Physics (Internet), 2024(9), p.091D01_1 - 091D01_13, 2024/09
被引用回数：0 パーセンタイル：0.00(Physics, Multidisciplinary)We conducted a measurement of the inclusive missing-mass spectrum in the C
reaction at an incident beam momentum of 1.8 GeV/. This measurement was carried out utilizing the Superconducting Kaon Spectrometer (SKS) and the K1.8 beamline spectrometer at the Hadron Experimental Hall in J-PARC. Remarkably, our experimental setup yielded an exceptionaly good energy resolution of 8.2 MeV (FWHM), enabling us to observe significant enhancements in the vicinity of the 
Be threshold region. In order to estimate the spectrum information, we employed several fitting parameters assumptions. The best agreement with the spectrum shape was obtained with combining quasi-free (QF) component and two-Gaussian functions, with the experimental resolution 
being held constant. The peak positions were obtained to be 
(stat.) 
(syst.) MeV and 
(stat.) 
(syst.) MeV. Another model assumption, utilizing quasi-free (QF) and one Breit-Wigner function with 
(stat.) 
(syst.) MeV and 
(stat.) 
(syst.) MeV, also yielded a similar 
value.
Josephson junctions and synchronized precession仲田 光樹; Zou, J.*; Klinovaja, J.*; Loss, D.*
Physical Review Research (Internet), 6(3), p.033207_1 - 033207_11, 2024/08
We uncover theoretically that a surprisingly rich dynamics can emerge in magnetic junctions due to intrinsic non-local damping, using analytical and numerical methods. In particular, under microwave pumping, we show that coherent spin precession in the right and left insulating ferromagnet (FM) of the junction becomes synchronized by non-local damping and thereby a magnonic analog of the Josephson junction emerges, where stands here for the relative precession phase of right and left FM in the stationary limit. Remarkably, decreases monotonically from 
to 
as the magnon-magnon interaction, arising from spin anisotropies, increases. Moreover, we also find a magnonic diode effect giving rise to rectification of magnon currents. Our predictions are readily testable with current device and measurement technologies at room temperatures.
細川 海慈*; 山 正樹*; 松尾 衛; 加藤 岳生*
Physical Review B, 110(3), p.035309_1 - 035309_12, 2024/07
被引用回数：2 パーセンタイル：0.00(Materials Science, Multidisciplinary)Our result provides an important foundation for an accurate analysis of the inverse Rashba-Edelstein effect induced by thermal spin injection.
船戸 匠*; 松尾 衛; 加藤 岳生*
Physical Review Letters, 132(23), p.236201_1 - 236201_7, 2024/06
被引用回数：6 パーセンタイル：82.50(Physics, Multidisciplinary)Our results clearly illustrate the microscopic origin of spin current generation by chiral phonons and may lead to a breakthrough in the development of spintronic devices without heavy elements.
佐野 涼太郎*; 大湊 友也*; 松尾 衛
Physical Review Letters, 132(23), p.236302_1 - 236302_9, 2024/06
被引用回数：4 パーセンタイル：82.50(Physics, Multidisciplinary)We propose an ac intrinsic magnon spin Hall current driven by surface acoustic waves as a novel probe for such antiferromagnets. Our results pave the way towards mechanical detection and manipulation of the magnetic order in two-dimensional antiferromagnets.
Yao, D.*; 松尾 衛; 横山 毅人*
Applied Physics Letters, 124(16), p.162603_1 - 162603_5, 2024/04
被引用回数：4 パーセンタイル：78.60(Physics, Applied)We propose a mechanism of spin current generation under an external electric field due to chiral phonons in a chiral-structure superconductor based on the Bogoliubov de Gennes and the Boltzmann equations.
藁科 友朗*; 佐藤 朝子*; 比内 浩; Shaikhutdinov, N.*; Shagimardanova, E.*; 森 宙史*; 玉木 聡志*; 斎藤 元文*; 眞田 幸尚; 佐々木 祥人; et al.
Applied and Environmental Microbiology, 90(4), p.e02113-23_1 - e02113-23_23, 2024/04
被引用回数：0 パーセンタイル：0.00(Biotechnology & Applied Microbiology)A major incident occurred at the Fukushima Daiichi Nuclear Power Station following the tsunami triggered by the Tohoku-Pacific Ocean Earthquake in March 2011, whereby seawater entered the torus room in the basement of the reactor building. Here, we identify and analyze the bacterial communities in the torus room water and several environmental samples. Samples of the torus room water (1 10
Bq
Cs/L) were collected by the Tokyo Electric Power Company Holdings from two sampling points between 30 cm and 1 m from the bottom of the room (TW1) and the bottom layer (TW2). A structural analysis of the bacterial communities based on 16S rRNA amplicon sequencing revealed that the predominant bacterial genera in TW1 and TW2 were similar. TW1 primarily contained the genus Limnobacter, a thiosulfate-oxidizing bacterium. 
-Irradiation tests on Limnobacter thiooxidans, the most closely related phylogenetically found in TW1, indicated that its radiation resistance was similar to ordinary bacteria. TW2 predominantly contained the genus Brevirhabdus, a manganese- oxidizing bacterium. Although bacterial diversity in the torus room water was lower than seawater near Fukushima, 
70% of identified genera were associated with metal corrosion. Latent environment allocation - an analytical technique that estimates habitat distributions and co-detection analyses - revealed that the microbial communities in the torus room water originated from a distinct blend of natural marine microbial and artificial bacterial communities typical of biofilms, sludge, and wastewater. Understanding the specific bacteria linked to metal corrosion in damaged plants is important for advancing decommissioning efforts.
FeO川本 陽*; 吉川 貴史; 齊藤 英治; 他9名*
Applied Physics Letters, 124(13), p.132406_1 - 132406_7, 2024/03
被引用回数：4 パーセンタイル：78.60(Physics, Applied)Magnon spin currents in the ferrimagnetic garnet Tb
Fe
O with 4
electrons were examined through the spin-Seebeck effect and neutron scattering measurements. The compound shows a magnetic compensation, where the spin-Seebeck signal reverses above and below 
= 249.5(4) K. Unpolarized neutron scattering unveils two major magnon branches with finite energy gaps, which are well explained in the framework of spin-wave theory. Their temperature dependencies and the direction of the precession motion of magnetic moments, i.e., magnon polarization, defined using polarized neutrons, explain the reversal at and decay of the spin-Seebeck signals at low temperatures. We illustrate an example that momentum- and energy-resolved microscopic information is a prerequisite to understand the magnon spin current.
水野 るり恵*; 新倉 潤*; 齋藤 岳志*; 松崎 禎市郎*; 櫻井 博儀*; Amato, A.*; 浅利 駿介*; Biswas, S.*; Chiu, I.-H.; Gianluca, J.*; et al.
Nuclear Instruments and Methods in Physics Research A, 1060, p.169029_1 - 169029_14, 2024/03
被引用回数：2 パーセンタイル：43.92(Instruments & Instrumentation)We have developed a photon detection system for muonic X-ray spectroscopy. The detector system consists of high-purity germanium detectors with BGO Compton suppressors. The signals from the detectors are readout with a digital acquisition system. The absolute energy accuracy, energy and timing resolutions, photo-peak efficiency, the performance of the Compton suppressor, and high count rate durability are studied with standard -ray sources and in-beam experiment using 
Al(
)
Si resonance reaction. The detection system was demonstrated at Paul Scherrer Institute. A calibration method for a photon detector at a muon facility using muonic X-rays of 
Au and 
Bi is proposed.
大湊 友也*; 山影 相*; 松尾 衛
Physical Review B, 109(12), p.L121405_1 - L121405_5, 2024/03
被引用回数：2 パーセンタイル：57.35(Materials Science, Multidisciplinary)We study a dynamical spin response of surface Majorana modes in a topological superconductor-magnet hybrid under microwave irradiation. We find a method to toggle between dissipative and nondissipative Majorana Ising spin dynamics by adjusting the external magnetic field angle and the microwave frequency. This reflects the topological nature of the Majorana modes, enhancing the Gilbert damping of the magnet, thereby providing a detection method for the Majorana Ising spins. Our findings illuminate a magnetic probe for Majorana modes, paving the path to innovative spin devices.
nuclei constrain element abundancesXian, W.*; 伊藤 由太; 他30名*
Physical Review C, 109(3), p.035804_1 - 035804_10, 2024/03
被引用回数：1 パーセンタイル：0.00(Physics, Nuclear)Atomic masses of the neutron-rich isotopes 
Ga, 
Ge, 
As, 
Se, 
Br, 
Kr, and 
Rb have been measured with high precision and accuracy using the multi-reflection time-of-flight mass spectrograph at the RIBF facility. The masses of 
As were measured for the first time and the mass uncertainties of 
Ge and 
Se were significantly reduced from several hundred keV to below the 10 keV scale. Investigation of shell evolution and potential subshell closures are proceeded by analysis of two-neutron separation energy systematics. As a result of the precise mass measurements, no prominent change on the slope of the two-neutron separation energy beyond 
is observed in Se isotopes, indicating the subshell closure effect at of Se does not exist. Also, various leading mass models are compared with the measurements. The impact of the more precisely known data on r-process nucleosynthesis calculations is investigated in light of these new mass measurements, showing a remarkable reduction of reaction-rate uncertainties.
谷口 耕治*; Huang, P.-J.*; 佐賀山 基*; 鬼柳 亮嗣; 大石 一城*; 鬼頭 俊介*; 中村 唯我*; 宮坂 等*
Physical Review Materials (Internet), 8(2), p.024409_1 - 024409_10, 2024/02
被引用回数：3 パーセンタイル：51.02(Materials Science, Multidisciplinary)Leveraging the flexible material designability of organic-inorganic hybrid systems, spatial inversion symmetry breaking and spin-orbit coupling (SOC) were simultaneously controlled in a series of two-dimensional organic-inorganic hybrid perovskite (2D-OIHP) copper halides with ferromagnetic exchange interaction (FMI). In chiral molecule-incorporated 2D-OIHP copper halides, an increase in Br component over Cl component at halogen sites leads to systematic variations in magnetic phase diagrams owing to the competition between the FMI and Dzyaloshinskii-Moriya interaction induced by the SOC. The crucial role of noncentrosymmetry in the competition for the magnetic interactions was confirmed by comparing the magnetic phase diagrams of chiral and achiral 2D-OIHP copper bromides.
松島 悠*; Zhang, Z.*; 大橋 由梨*; 畠山 紘*; Xiao, G.*; 船戸 匠*; 松尾 衛; 海住 英生*
Applied Physics Letters, 124(2), p.022404_1 - 022404_7, 2024/01
被引用回数：3 パーセンタイル：70.50(Physics, Applied)We report the discovery of a stepwise magnetic field-induced emergent magneto-inductance effect in Permalloy thin films deposited on polycarbonate substrates. This study opens up exciting avenues for advancing our understanding of emergent inductance in fundamental physics and paves the way for practical applications in flexible magnetic devices.
服部 恒一*; 末永 大輝*; 鈴木 渓; 安井 繁宏*
Physical Review B, 108(24), p.245110_1 - 245110_11, 2023/12
被引用回数：2 パーセンタイル：25.54(Materials Science, Multidisciplinary)通常の近藤効果は、伝導電子と交換相互作用を行う不純物を含んだ金属中で起こり、伝導電子のフェルミ面の存在が重要となるが、フェルミ面を持たない系における類似した現象の解明は近藤効果の基礎的理解のために重要である。さらに、通常の近藤効果は磁場中で抑制されるが、とある条件の下では磁場によって増幅することも起こりえる。本論文では、フェルミ面を持たない系において強磁場の存在に起因する近藤効果を記述するための模型を構築・提案する。この模型では、物質中を伝導するディラック粒子と物質内部で局在する不純物から成る粒子対である「近藤凝縮」を平均場として仮定することで、それを秩序変数とする相図を決定することができる。一方で、ディラック粒子・反粒子の粒子対として定義される「カイラル凝縮」は、クォーク系においては古くから知られた基底状態であるが、相互作用するディラック電子系においても類似した基底状態の存在が期待されている。さらに、ディラック粒子・反粒子間に極小の引力相互作用さえあれば、磁場の大きさに伴ってカイラル凝縮が(一般的には)増幅する現象が知られており、magnetic catalysis(磁気触媒機構)と呼ばれている。このため、本研究ではカイラル凝縮と近藤凝縮との磁場中での競合効果に注目し、この競合効果によって磁場をパラメータとする相図上に量子臨界点が現れることを予言した。さらに、磁場だけでなく有限温度の相図の予言も行った。フェルミ面に起因する通常の近藤効果とは異なり、強磁場のみによって誘起される近藤系はモンテカルロ法における負符号問題を持たないため、モンテカルロシミュレーションによって将来的に高精度の検証がなされることが期待される。
