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arXiv · 2210.06775

Quantum anomalous Hall effects controlled by chiral domain walls

Abstract

We report the interplay between two different topological phases in condensed matter physics, the magnetic chiral domain wall (DW), and the quantum anomalous Hall (QAH) effect. We show that the chiral DW driven by Dzyaloshinskii-Moriya interaction (DMI) can divide the uniform domain into several zones where the neighboring zone possesses opposite quantized Hall conductance. The separated domain with a chiral edge state (CES) can be continuously modified by external magnetic field-induced domain expansion and thermal fluctuation, which gives rise to the reconfigurable QAH effect. More interestingly, we show that the position of CES can be tuned by spin current-driven chiral DW motion. Several two-dimensional magnets with high Curie temperatures and large topological band gaps are proposed for realizing these phenomena. Our work thus reveals the possibility of chiral DW controllable QAH effects.

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Qirui Cui, Jinghua Liang, Yingmei Zhu, Xiong Yao, Hongxin Yang. 2022-10-13. Quantum anomalous Hall effects controlled by chiral domain walls. https://doi.org/10.1088/0256-307x%2F40%2F3%2F037502

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