Disordered Weyl semimetals and their topological family

Y. X. Zhao; Z. D. Wang

doi:10.1103/physrevlett.114.206602

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arXiv · 1412.7678

Disordered Weyl semimetals and their topological family

Y. X. Zhao·Z. D. Wang

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Abstract

We develop a topological theory for disordered Weyl semimetals in the framework of gauge invariance of replica formalism and boundary-bulk correspondence of Chern insulators. An anisotropic topological $\theta$-term is analytically derived for the effective non-linear sigma model. It is this nontrivial topological term that ensures the bulk transverse transport of Weyl semimetals to be robust against disorders. Moreover, we establish a general diagram that reveals the intrinsic relations among topological terms in the non-linear sigma models and gauge response theories respectively for $(2n + 2)$-dimensional topological insulators, $(2n+1)$-dimensional chiral fermions, $(2n+1)$-dimensional chiral semimetals, and $(2n)$-dimensional topological insulators with $n$ being a positive integer.

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Y. X. Zhao, Z. D. Wang. 2014-12-24. Disordered Weyl semimetals and their topological family. https://doi.org/10.1103/physrevlett.114.206602

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