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Ishida, Takekazu*; Vu, TheDang*; Shishido, Hiroaki*; Aizawa, Kazuya; Oku, Takayuki; Oikawa, Kenichi; Harada, Masahide; Kojima, Kenji M*; Miyajima, Shigeyuki*; Koyama, Tomio*; et al.
Journal of Low Temperature Physics, 214(3-4), p.152 - 157, 2024/02
Times Cited Count:0 Percentile:0.01(Physics, Applied)Shishido, Hiroaki*; Vu, TheDang*; Aizawa, Kazuya; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Oku, Takayuki; Soyama, Kazuhiko; Miyajima, Shigeyuki*; et al.
Journal of Applied Crystallography, 56(4), p.1108 - 1113, 2023/08
Times Cited Count:0 Percentile:0.02(Chemistry, Multidisciplinary)Araki, Yasufumi; Ieda, Junichi
Journal of the Physical Society of Japan, 92(7), p.074705_1 - 074705_9, 2023/06
Times Cited Count:0 Percentile:0(Physics, Multidisciplinary)Topological electromagnetism owing to nontrivial momentum-space topology of electrons in insulators gives rise to diverse anomalous magnetoelectric responses. While conventional inductors and capacitors are based on classical electromagnetism described by Maxwell's equations, here we show that topological electromagnetism in combination with spin dynamics in magnets also generates an inductance or a capacitance. We build a generic framework to extract the complex impedance on the basis of topological field theory, and demonstrate the emergence of an inductance or a capacitance in several heterostructure setups. In comparison with the previously-studied emergent inductances in metallic magnets, insulators highly suppress the power loss, because of the absence of Joule heating. We show that the inductance from topological electromagnetism is achieved at low current and high frequency, and is also advantageous in its power efficiency, as characterized by the high quality factor (Q-factor).
Yamane, Yuta*; Fukami, Shunsuke*; Ieda, Junichi
Physical Review Letters, 128(14), p.147201_1 - 147201_6, 2022/04
Times Cited Count:3 Percentile:56.47(Physics, Multidisciplinary)We extend the theory of emergent inductance, which has recently been discovered in spiral magnets, to arbitrary magnetic textures by taking into account spin-orbit couplings arising in the absence of spatial inversion symmetry. We propose a new concept of spin-orbit emergent inductance, which can be formulated as originating from a dynamical Aharonov-Casher phase of an electron in ferromagnets. The spin-orbit emergent inductance universally arises in the coexistence of magnetism and the spin-orbit couplings, even with spatially uniform magnetization, allowing its stable operation in wide ranges of temperature and frequency. Revisiting the widely studied systems involving ferromagnets with spatial inversion asymmetry, with the new perspective offered by our work, will lead to opening a new paradigm in the study of spin-orbit physics and the spintronics-based power management in ultrawideband frequency range.
Shishido, Hiroaki*; Nishimura, Kazuma*; Vu, TheDang*; Aizawa, Kazuya; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Oku, Takayuki; Soyama, Kazuhiko; et al.
IEEE Transactions on Applied Superconductivity, 31(9), p.2400505_1 - 2400505_5, 2021/12
Times Cited Count:0 Percentile:0(Engineering, Electrical & Electronic)In this study, we employed a superconducting detector, current-biased kinetic-inductance detector (CB-KID) for neutron imaging using a pulsed neutron source. We employed the delay-line method, and high spatial resolution imaging with only four reading channels was achieved. We also performed wavelength-resolved neutron imaging by the time-of-flight method. We obtained the neutron transmission images of a Gd-Al alloy sample, inside which single crystals of GdAl were grown, using the delay-line CB-KID. Single crystals were well imaged, in both shapes and distributions, throughout the Al-Gd alloy. We identified Gd nuclei via neutron transmissions that exhibited characteristic suppression above the neutron wavelength of 0.03 nm. In addition, the Gd resonance dip, a dip structure of the transmission caused by the nuclear reaction between an isotope and neutrons, was observed even when the number of events was summed over a limited area of 15 m 12 m. Gd selective imaging was performed using the resonance dip of Gd, and it showed clear Gd distribution even with a limited neutron wavelength range of 1 pm.
Ieda, Junichi; Yamane, Yuta*
Physical Review B, 103(10), p.L100402_1 - L100402_5, 2021/03
Times Cited Count:15 Percentile:78.56(Materials Science, Multidisciplinary)Shishido, Hiroaki*; Nishimura, Kazuma*; Vu, TheDang*; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Miyajima, Shigeyuki*; Hidaka, Mutsuo*; Oku, Takayuki; et al.
Journal of Physics; Conference Series, 1590, p.012033_1 - 012033_8, 2020/10
Times Cited Count:0 Percentile:0.01(Engineering, Electrical & Electronic)Takayanagi, Tomohiro; Ueno, Tomoaki; Horino, Koki
Journal of Physics; Conference Series, 1350(1), p.012183_1 - 012183_7, 2019/12
Times Cited Count:0 Percentile:0.06(Physics, Particles & Fields)As one of the advanced research and development for maintaining the stable operation of J-PARC RCS, we are developing semiconductor switch circuit for thyratron substitute adopted in kicker system. Radiation symmetric type circuits using semiconductors of SIC-MOSFETs are composed of circuits in which many semiconductor switches are multiplexed in parallel. Since the lengths of all parallel circuits are equal, the output waveform will not be distorted due to timing jitter or impedance. This circuit is useful for outputting the waveform of ultrafast short pulse. Therefore, we have developed a circuit that achieves further low inductance by making the power transmission circuit into a double circular ring structure equal to the coaxial shape. Compare the inductance value obtained from the structure and the output waveform. In addition, we compare the calculation and the measurement in the test and present the verification result of the developed circular ring structure.
Iizawa, Yuki*; Shishido, Hiroaki*; Nishimura, Kazuma*; Vu, TheDang*; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Miyajima, Shigeyuki*; Hidaka, Mutsuo*; et al.
Superconductor Science and Technology, 32(12), p.125009_1 - 125009_8, 2019/12
Times Cited Count:13 Percentile:58.41(Physics, Applied)Matsuoka, Mamoru; JT-60 Team
Fusion Engineering and Design, 26(1-4), p.59 - 68, 1995/01
Times Cited Count:2 Percentile:28.04(Nuclear Science & Technology)no abstracts in English
Tamai, Hiroshi; Shoji, Teruaki; Nagashima, Keisuke; Miura, Yukitoshi; Yamauchi, Toshihiko; Ogawa, Hiroaki; Kawashima, Hisato; Matsuda, Toshiaki; Mori, Masahiro; *; et al.
Journal of Nuclear Materials, 220-222, p.365 - 369, 1995/00
Times Cited Count:17 Percentile:82.2(Materials Science, Multidisciplinary)no abstracts in English
Kamada, Yutaka; Takizuka, Tomonori; Kikuchi, Mitsuru; Ninomiya, Hiromasa
Nuclear Fusion, 33(2), p.225 - 236, 1993/00
Times Cited Count:19 Percentile:55.85(Physics, Fluids & Plasmas)no abstracts in English
; ; *; *; *; *
Fujikura Densen Giho, 66(9), p.101 - 104, 1983/00
no abstracts in English
; ;
Denki Gakkai Rombunshi, A, 99A(2), p.49 - 56, 1979/00
no abstracts in English
Machida, Masahiko; Ota, Yukihiro
no journal, ,
Fluctuations significantly alter the conventional picture on transport phenomena in 1D superconductors. We study the current-dependence of the kinetic inductance in superconducting wires using the Ginzuburg-Landau approach with fluctuations. We obtain a non-monotonic current-dependence of the kinetic inductance when the thermal fluctuations predominate the behaviors of the superconducting phase. This result is ascribed to the occurrence of phase-slip centers from thermally-activated processes. We also find that our approach qualitatively reproduces the experiment by Annunziata et al. Moreover, we discuss the effects of thermal fluctuations on the characteristics of superconducting detectors. We will also discuss the effects of quantum phase slips on superconducting detectors.
Yamane, Yuta*; Ieda, Junichi
no journal, ,
no abstracts in English
Ieda, Junichi; Yamane, Yuta*
no journal, ,
no abstracts in English
Ieda, Junichi; Yamane, Yuta*
no journal, ,
no abstracts in English