Surface structure and surface state of a tight-binding model on a diamond lattice

Kubo, Katsunori

Journal of the Physical Society of Japan, 94(7), p.074701_1 - 074701_5, 2025/07

https://doi.org/10.7566/JPSJ.94.074701

Distinguishing ion dynamics from muon diffusion in muon spin relaxation II; Extension to paramagnetic muons

Kadono, Ryosuke*; Ito, Takashi

Journal of the Physical Society of Japan, 94(6), p.064601_1 - 064601_11, 2025/06

https://doi.org/10.7566/JPSJ.94.064601

Neutron spectroscopy study on crystalline electric field excitations in NdB

Yamauchi, Hiroki; Metoki, Naoto; Watanuki, Ryuta*; Hong, T.*; Fernandez-Baca, J. A.*; Hagihara, Masato; Masuda, Takatsugu*; Yoshizawa, Hideki*; Ito, Shinichi*

Journal of the Physical Society of Japan, 94(5), p.054705_1 - 054705_8, 2025/04

https://doi.org/10.7566/JPSJ.94.054705

The Influence of structural dynamics in two-dimensional hybrid organic-inorganic perovskites on their photoluminescence efficiency; Neutron scattering analysis

Rajeev, H. S.*; Hu, X.*; Chen, W.-L.*; Zhang, D.*; Chen, T.*; Kofu, Maiko*; Kajimoto, Ryoichi; Nakamura, Mitsutaka; Chen, A. Z.*; Johnson, G. C.*; et al.

Journal of the Physical Society of Japan, 94(3), p.034602_1 - 034602_14, 2025/03

https://doi.org/10.7566/JPSJ.94.034602

Self-learning Monte Carlo with equivariant Transformer

Nagai, Yuki; Tomiya, Akio*

Journal of the Physical Society of Japan, 93(11), p.114007_1 - 114007_8, 2024/11

https://doi.org/10.7566/JPSJ.93.114007

We proposed a new self-learning Monte Carlo method using Transformer, a key technology in generative AI. By using Transformer's Attention mechanism, which can infer the relevance of distant words in a sentence, we have constructed an effective model that can efficiently capture the long-range correlations that are important in the phase transitions in electronic systems. Furthermore, we reduce the number of parameters by incorporating symmetries that the system must satisfy, such as spin rotation and spatial translation, into the network. We also found a scaling law that the loss decreases as the number of layers is increased.

Polarized and unpolarized neutron scattering for magnetic materials at the triple-axis spectrometer PONTA in JRR-3

Nakajima, Taro*; Saito, Hiraku*; Kobayashi, Naoki*; Kawasaki, Takuro; Nakamura, Tatsuya; Furukawa, Hazuki*; Asai, Shinichiro*; Masuda, Takatsugu*

Journal of the Physical Society of Japan, 93(9), p.091002_1 - 091002_5, 2024/09

https://doi.org/10.7566/JPSJ.93.091002

Chiral gauge field in fully spin-polarized magnetic Weyl semimetal with magnetic domain walls

Ozawa, Akihiro*; Araki, Yasufumi; Nomura, Kentaro*

Journal of the Physical Society of Japan, 93(9), p.094704_1 - 094704_9, 2024/09

https://doi.org/10.7566/JPSJ.93.094704

Modulation of magnetization in magnetic Weyl semimetals leads to the shift of Weyl points in momentum space, which effectively serves as the chirality-dependent gauge field for the Weyl fermions. Here, we theoretically study such a magnetization-induced chiral gauge field, in a fully spin-polarized Weyl ferromagnet CoSnS. From a tight-binding model of CoSnS on stacked kagome lattice with magnetism, we calculate the magnetization-dependent evolution of the Weyl points in momentum space, resulting in the chiral gauge field. In the presence of the magnetic domain wall structure, we evaluate the chiral magnetic field arising from the spatial profile of the chiral gauge field. We find that a magnetic domain wall in CoSnS gives rise to a giant chiral magnetic field for the Weyl fermions, which reaches the order of a few hundred tesla to induce the Landau quantization. Such a giant chiral magnetic field may also influence the novel transport phenomena, such as the charge pumping by the domain wall motion, compatible with the spinmotive force.

Polarized neutron diffraction study on UPtSi

Kon, Fusako*; Tabata, Chihiro; Saito, Hiraku*; Nakajima, Taro*; Hidaka, Hiroyuki*; Yanagisawa, Tatsuya*; Amitsuka, Hiroshi*

Journal of the Physical Society of Japan, 93(4), p.044701_1 - 044701_11, 2024/04

https://doi.org/10.7566/JPSJ.93.044701

Weyl semimetallic state in the Rashba-Hubbard Model

Kubo, Katsunori

Journal of the Physical Society of Japan, 93(2), p.024708_1 - 024708_8, 2024/02

https://doi.org/10.7566/JPSJ.93.024708

Isotopic composition of enriched Mo for production of medical Tc by Mo()Tc

Hashimoto, Shintaro; Nagai, Yasuki*

Journal of the Physical Society of Japan, 92(12), p.124202_1 - 124202_11, 2023/12

https://doi.org/10.7566/JPSJ.92.124202

Tc, which is a daughter nuclide of Mo, is used worldwide for medical imaging. However, there is a problem with the supply of Tc (Mo) due to the replacement of aging reactors. A method to produce Tc by irradiating Mo with protons using medical cyclotrons has been proposed. In this study, we presented a method to determine individual excitation functions for Mo()Tc using measured excitation functions for Mo()Tc. The method was validated by comparing estimated radionuclide purities of Tc in enriched Mo samples using the determined excitation functions with measured ones. In this study, we found that the content of Mo, Mo, and Mo should be low in order to produce Tc with high radionuclide purity. The results of this study play an important role in discussion of the required Mo compositions in enriched Mo, taking into account the constraints of each facility.