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arXiv · 1008.2666

Topological Magnetic Insulators with Corundum Structure

Jing Wang·Rundong Li·Shou-Cheng Zhang·Xiao-Liang Qi
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Abstract

Topological insulators are new states of quantum matter in which surface states residing in the bulk insulating gap are protected by time-reversal symmetry. When a proper kind of antiferromagnetic long range order is established in a topological insulator, the system supports axionic excitations. In this paper, we study theoretically the electronic states in a transition metal oxide of corundum structure, in which both spin-orbit interaction and electron-electron interaction play crucial roles. A tight-binding model analysis predicts that materials with this structure can be strong topological insulator. Because of the electron correlation, an antiferromagnetic order may develop, giving rise to a topological magnetic insulator phase with axionic excitations.

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Jing Wang, Rundong Li, Shou-Cheng Zhang, Xiao-Liang Qi. 2010-08-16. Topological Magnetic Insulators with Corundum Structure. https://doi.org/10.1103/physrevlett.106.126403

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