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arXiv · 2108.03928

Anti-commutative dynamical magneto-electric response in certain solid state materials

Maoyuan Wang·Haiwen Liu·X. C. Xie
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Abstract

Axion field induced topological magneto-electric response has attracted lots of attentions since it was first proposed by Qi et al. in 2008. Here we find a new type of anti-commutative magneto-electric response \beta^{\xi}(\omega), which can induce a dynamical magneto-electric current driven by a time-varying magnetic field. Unlike the Chern-Simons Axion term, this magneto-electric response term is gauge-independent and non-quantized, and manifests in the systems breaking the symmetries of the time-reversal, inversion and mirror. In particular, we propose the antiferromagnetic material Mn_{2}Bi_{2}Te_{5} as a material candidate to observe dynamical magneto-electric current, in which a large magneto-electric response term \beta^{\xi}(\omega) originates from band inversion.

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Maoyuan Wang, Haiwen Liu, X. C. Xie. 2021-08-09. Anti-commutative dynamical magneto-electric response in certain solid state materials. https://doi.org/10.1103/physrevlett.128.236601

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