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arXiv · 2004.04862

Alloying V in MnBi$_2$Te$_4$ for Robust Ferromagnetic Coupling and Quantum Anomalous Hall Effect

Y. S. Hou·R. Q. Wu
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Abstract

The intrinsic antiferromagnetic (AFM) interlayer coupling in two-dimensional magnetic topological insulator MnBi$_2$Te$_4$ places a restriction on realizing stable quantum anomalous Hall effect (QAHE) [Y. Deng et al., Science 367, 895 (2020)]. Through density functional theory calculations, we demonstrate the possibility of tuning the AFM coupling to the ferromagnetic coupling in MnBi$_2$Te$_4$ films by alloying about 50% V with Mn. As a result, QAHE can be achieved without alternation with the even or odd septuple layers. This provides a practical strategy to get robust QAHE in ultrathin MnBi$_2$Te$_4$ films, rendering them attractive for technological innovations.

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Y. S. Hou, R. Q. Wu. 2020-04-16. Alloying V in MnBi$_2$Te$_4$ for Robust Ferromagnetic Coupling and Quantum Anomalous Hall Effect. https://doi.org/10.1103/physrevb.103.064412

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