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arXiv · 1404.7535

Equilibrium currents in chiral systems with non-zero Chern number

E. G. Mishchenko·O. A. Starykh
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Abstract

We describe simple quantum-mechanical approach to calculating equilibrium particle current along the edge of a system with non-trivial band spectrum topology. The approach does not require any a priori knowledge of the band topology and, as a matter of fact, treats topological and non-topological contributions to the edge currents on the same footing. We illustrate its usefulness by demonstrating the existence of `topologically non-trivial' particle currents along the edges of three different physical systems: two-dimensional electron gas with spin-orbit coupling and Zeeman magnetic field, surface state of a topological insulator, and kagome antiferromagnet with Dzyaloshinskii-Moriya interaction. We describe relation of our results to the notion of orbital magnetization.

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E. G. Mishchenko, O. A. Starykh. 2014-04-29. Equilibrium currents in chiral systems with non-zero Chern number. https://doi.org/10.1103/physrevb.90.035114

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