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arXiv · 2211.08163

Intrinsic and tunable quantum anomalous Hall effect and magnetic topological phases in XYBi2Te5

Xin-Yi Tang·Zhe Li·Feng Xue·Pengfei Ji·Zetao Zhang·Xiao Feng·Yong Xu·Quansheng Wu·Ke He
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Abstract

By first-principles calculations, we study the magnetic and topological properties of XYBi2Te5-family (X, Y = Mn, Ni, V, Eu) compounds. The strongly coupled double magnetic atom-layers can significantly enhance the magnetic ordering temperature while keeping the topologically nontrivial properties. Particularly, NiVBi2Te5 is found to be a magnetic Weyl semimetal in bulk and a Chern insulator in thin film with both the Curie temperature (~150 K) and full gap well above 77 K. Ni2Bi2Te5, MnNiBi2Te5, NiVBi2Te5 and NiEuBi2Te5 exhibits intrinsic dynamic axion state. Among them, MnNiBi2Te5 has a Neel temperature over 200 K and Ni2Bi2Te5 even demonstrates antiferromagnetic order above room temperature. These results indicate an approach to realize high temperature quantum anomalous Hall effect and other topological quantum effects for practical applications.

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Xin-Yi Tang, Zhe Li, Feng Xue, Pengfei Ji, Zetao Zhang, Xiao Feng, Yong Xu, Quansheng Wu, Ke He. 2022-11-15. Intrinsic and tunable quantum anomalous Hall effect and magnetic topological phases in XYBi2Te5. https://doi.org/10.1103/physrevb.108.075117

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