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Parity (and time-reversal) anomaly in a semiconductor

Oleg Tchernyshyov
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Abstract

The physics of a parity anomaly, potentially observable in a narrow-gap semiconductor, is revisited. Fradkin, Dagotto, and Boyanovsky have suggested that a Hall current of anomalous parity can be induced by a Peierls distortion on a domain wall. I argue that a perturbation inducing the parity anomaly must break the time reversal symmetry, which rules out the Peierls distortion as a potential cause. I list all possible perturbations that can generate the anomaly.

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Oleg Tchernyshyov. 2000-10-30. Parity (and time-reversal) anomaly in a semiconductor. https://doi.org/10.1103/physrevb.62.16751

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