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arXiv · 1910.11730

A diagnosis scheme for topological degeneracies at high-symmetry momenta

Tiantian Zhang·Ling Lu·Shuichi Murakami·Zhong Fang·Hongming Weng·Chen Fang
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Abstract

Theories of symmetry-based indicators and topological quantum chemistry, while powerful in diagnosing gapped topological materials, cannot be directly applied to diagnosing band degeneracies at high-symmetry momenta due to the violation of the compatibility conditions. Here we design a recursive protocol that utilizes indicators of maximal subgroups to infer the topological nature of band degeneracies at high-symmetry lines. For demonstration, the method is used to predict the existence of iso-energy Weyl points and a node-line cage, respectively, in the phonon bands of In2Te and ZrSiO.

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Tiantian Zhang, Ling Lu, Shuichi Murakami, Zhong Fang, Hongming Weng, Chen Fang. 2019-10-25. A diagnosis scheme for topological degeneracies at high-symmetry momenta. https://doi.org/10.1103/physrevresearch.2.022066

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