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arXiv · 2201.07991

Chiral anomaly in non-relativistic systems: Berry curvature and chiral kinetic theory

Lan-Lan Gao·Xu-Guang Huang
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Abstract

Chiral anomaly and the novel quantum phenomena it induces have been widely studied for Dirac and Weyl fermions. In most typical cases, the Lorentz covariance is assumed and thus the linear dispersion relations are maintained. However, in realistic materials, such as Dirac and Weyl semimetals, the non-linear dispersion relations appear naturally. We develop a kinetic framework to study the chiral anomaly for Weyl fermions with non-linear dispersions by using the methods of Wigner function and semi-classical equations of motion. In this framework, the chiral anomaly is sourced by Berry monopoles in momentum space and could be enhanced or suppressed due to the windings around the Berry monopoles. Our results can help understand the chiral anomaly-induced transport phenomena in non-relativistic systems.

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Lan-Lan Gao, Xu-Guang Huang. 2022-01-20. Chiral anomaly in non-relativistic systems: Berry curvature and chiral kinetic theory. https://doi.org/10.1088/0256-307x%2F39%2F2%2F021101

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