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arXiv · 1112.5789

Interaction-driven topological and nematic phases on the Lieb lattice

Wei-Feng Tsai·Chen Fang·Hong Yao·JiangPing Hu
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Abstract

We show that topological states are often developed in two dimensional semimetals with quadratic band crossing points (BCPs) by electron-electron interactions. To illustrate this, we construct a concrete model with the BCP on an extended Lieb lattice and investigate the interaction-driven topological instabilities. We find that the BCP is marginally unstable against infinitesimal repulsions. Depending on the interaction strengths, topological quantum anomalous/spin Hall, charge nematic, and nematic-spin-nematic phases, develop separately. Possible physical realizations of quadratic BCPs are provided.

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Wei-Feng Tsai, Chen Fang, Hong Yao, JiangPing Hu. 2015-05-15. Interaction-driven topological and nematic phases on the Lieb lattice. https://arxiv.org/abs/1112.5789

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