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arXiv · 1804.01027

Topological properties of magnetically ordered heavy-fermion systems in the presence of mirror symmetry

Kazuhiro Kimura·Tsuneya Yoshida·Norio Kawakami
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Abstract

We explore topological states with magnetic order in heavy-fermion systems by taking account of a mirror symmetry.Although without spatial symmetry, there is no topological phase in the two-dimensional (2D) antiferromagnetic phases at half filling, we demonstrate that a topological phase emerges in the presence of mirror symmetry.This is explicitly shown for a two-dimensional periodic Anderson model.Furthermore, our analysis around quarter filling shows that a half-metallic state emerges in the ferromagnetic phase, where a spin-selective gap opens, resulting in nontrivial properties characterized by a Chern number.In contrast to the previously proposed models, our scenario can apply even for spin nonconserving systems in the presence of spin-orbit coupling.

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Kazuhiro Kimura, Tsuneya Yoshida, Norio Kawakami. 2018-04-03. Topological properties of magnetically ordered heavy-fermion systems in the presence of mirror symmetry. https://doi.org/10.7566/jpsj.87.084705

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