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arXiv · 1211.0772

Topological Invariants of Metals and Related Physical Effects

Jianhui Zhou·Hua Jiang·Qian Niu·Junren Shi
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Abstract

The total reciprocal space magnetic flux threading through a closed Fermi surface is a topological invariant for a three-dimensional metal. For a Weyl metal, the invariant is non-zero for each of its Fermi surfaces. We show that such an invariant can be related to magneto-valley-transport effect, in which an external magnetic field can induce a valley current. We further show that a strain field can drive an electric current, and the effect is dictated by a second class Chern invariant. These connections open the pathway to observe the hidden topological invariants in metallic systems.

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Jianhui Zhou, Hua Jiang, Qian Niu, Junren Shi. 2012-11-05. Topological Invariants of Metals and Related Physical Effects. https://doi.org/10.1088/0256-307x%2F30%2F2%2F027101

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