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arXiv · 2207.14125

Signature of parity anomaly in the measurement of optical Hall conductivity in quantum anomalous Hall systems

Zi-Ang Hu·Huan-Wen Wang·Bo Fu·Jin-Yu Zou·Shun-Qing Shen
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Abstract

Parity anomaly is a quantum mechanical effect that the parity symmetry in a two-dimensional classical action is failed to be restored in any regularization of the full quantum theory and is characterized by a half-quantized Hall conductivity. Here we propose a scheme to explore the experimental signature from parity anomaly in the measurement of optical Hall conductivity, in which the optical Hall conductivity is nearly half quantized for a proper range of frequency. The behaviors of optical Hall conductivity are studied for several models, which reveal the appearance of half-quantized Hall conductivity in low or high-frequency regimes. The optical Hall conductivity can be extracted from the measurement of Kerr and Faraday rotations and the absorption rate of the circularly polarized light. This proposal provides a practical method to explore the signature of parity anomaly in topological quantum materials.

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Zi-Ang Hu, Huan-Wen Wang, Bo Fu, Jin-Yu Zou, Shun-Qing Shen. 2022-07-28. Signature of parity anomaly in the measurement of optical Hall conductivity in quantum anomalous Hall systems. https://doi.org/10.1103/physrevb.106.035149

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