[20a-D61-1~9] 10.1 新物質・新機能創成（作製・評価技術）

9:00 〜 9:15英語発表注目講演

[20a-D61-1] Room-temperature flexible manipulation of the quantum-metric structure in a topological chiral antiferromagnet

〇Jiahao Han^1,2, Tomohiro Uchimura^1,3, Yasufumi Araki⁴, Ju-Young Yoon^1,3, Yutaro Takeuchi², Yuta Yamane^1,5, Shun Kanai^{1,2,3,6,7,8,9}, Junichi Ieda⁴, Hideo Ohno^1,2,3,8,10, Shunsuke Fukami^1,2,3,8,11 (1.RIEC, Tohoku Univ., 2.AIMR, Tohoku Univ., 3.Eng., Tohoku Univ., 4.ASRC, JAEA, 5.FRIS, Tohoku Univ., 6.PRESTO, JST., 7.DEFS, Tohoku Univ., 8.CSIS, Tohoku Univ., 9.QST, 10.CIES, Tohoku Univ., 11.InaRIS)

キーワード：

Quantum metric、Chiral antiferromagnet、Second-order Hall effect

The quantum metric and Berry curvature are two fundamental and distinct factors that describe the geometry of quantum eigenstates. While the role of the Berry curvature in governing various condensed-matter states has been investigated extensively, the quantum metric, which was also predicted to induce topological phenomena of equal importance, has rarely been studied. Recently, a breakthrough has been made in observing the quantum-metric nonlinear transport in a van der Waals magnet, but the effect is limited at cryogenic temperature and is tuned by strong magnetic fields of several teslas. In our study, we demonstrate room-temperature manipulation of the quantum-metric structure of electronic states through its interplay with the interfacial spin texture in a topological chiral antiferromagnet/heavy metal Mn₃Sn/Pt heterostructure, which is manifested in a time-reversal-odd second-order Hall effect (ScHE). We show the flexibility of controlling the quantum-metric structure with moderate magnetic fields and verify the quantum-metric origin of the observed ScHE by theoretical modeling. Our results open the possibility of building applicable nonlinear devices by harnessing the quantum-metric structure of electronic states.