The interplay of magnetism and topology offers great opportunities to explore variant emerging topological quantum phenomena. Here we will present that van der Waals layered MnBi₂Te₄-related materials intrinsically host nontrivial band topology, which possess A-type antiferromagnetism characterized by ferromagnetic intralayer and antiferromagnetic interlayer coupling. Extremely rich 2D and 3D topological quantum states emerge in MnBi₂Te₄, including 3D antiferromagnetic topological insulator with the long-sought topological axion states on the surface, the simple magnetic Weyl semimetal with one pair of Weyl points, as well as intrinsic axion insulators and QAH insulators in even- and odd-layer films, respectively [1]. Furthermore, we will show a series of magnetically controllable topological quantum phase transitions in the material [2]. Relevant experimental progresses will also be introduced [3-5].
[1] J. Li et al., Sci. Adv. 5, eaaw5685 (2019)
[2] J. Li et al., Phys. Rev. B 100, 121103(R) (2019)
[3] Y. Gong et al., Chin. Phys. Lett. 36, 7 (2019)
[4] C. Liu et al., arXiv: 1905.00715
[5] J. Ge et al., arXiv: 1907.09947