2026-05-18 東京大学,理化学研究所,科学技術振興機構
原子層反強磁性体における磁気状態を反映した新しい光電流
＜関連情報＞
- https://www.issp.u-tokyo.ac.jp/maincontents/news2.html?pid=30572
- https://www.nature.com/articles/s41563-026-02593-8
パリティ・時間対称性を持つ二次元反強磁性体における層状光起電力効果 Layer photovoltaic effect in a two-dimensional antiferromagnet with parity–time symmetry
Yu Dong,Sota Kitamura,Yuki M. Itahashi,Daniel G. Chica,Shingo Toyoda,Kenji Watanabe,Takashi Taniguchi,Miuko Tanaka,Xavier Roy,Naoki Ogawa,Takahiro Morimoto,Yoshihiro Iwasa & Toshiya Ideue
Nature Materials Published:18 May 2026
DOI:https://doi.org/10.1038/s41563-026-02593-8
Abstract
Antiferromagnets with parity–time symmetry host intriguing optical and transport phenomena governed by quantum metric, as the counterpart, Berry curvature, vanishes under parity–time symmetry. In antiferromagnets with parity–time symmetry, the intrinsic photovoltaic effect, driven by the interband quantum metric associated with optically allowed transitions, is expected due to the inversion symmetry breaking induced by antiferromagnetic order, but experimental demonstration has remained elusive. Here we report the experimental observation of an intrinsic photovoltaic effect in a two-dimensional antiferromagnet with parity–time symmetry, bilayer CrSBr. Notably, the intrinsic photocurrent reverses sign according to the antiferromagnetic configurations. Moreover, by manipulating the magnetic field and device architecture (the top and bottom contacts), we distinctly identify layer-resolved intrinsic photocurrent responses. A tight-binding model based on the band-resolved quantum-metric-driven magnetic injection current mechanism is proposed to interpret these observations and reveal the layer-localized nature of the quantum metric. Our findings provide a promising strategy for developing switchable photovoltaic devices and engineering the spatial quantum geometry in layered antiferromagnets.
