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arXiv · 1709.09316

Instability and topological robustness of Weyl semimetals against Coulomb interaction

Fei Xue·Xiao-Xiao Zhang
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Abstract

There is a close connection between various new phenomena in Weyl semimetals and the existence of linear band crossings in the single particle description. We show, by a full self-consistent mean-field calculation, how this picture is modified in the presence of long-range Coulomb interactions. The chiral symmetry breaking occurs at strong enough interactions and the internode interband excitonic pairing channel is found to be significant, which determines the gap-opened band profile varying with interaction strength. Remarkably, in the resultant interacting phase, finite band Chern number jumps in the three-dimensional momentum space are retained, indicating the robustness of the topologically nontrivial features.

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Fei Xue, Xiao-Xiao Zhang. 2017-11-24. Instability and topological robustness of Weyl semimetals against Coulomb interaction. https://doi.org/10.1103/physrevb.96.195160

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