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arXiv · 1504.02296

Effects of Attractive correlation on Topological Flat-bands Model

Chun-Li Zang·Jing He·Ya-Jie Wu
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Abstract

In this paper, we study the effects of attractive correlation on the topological insulator ($TI$) with topological flat-bands using an extended attractive Kane-Mele-Hubbard model (KMHM). In the KMHM, we found a quantum phase transition from $TI$ to the superconductor ($SC$) state upon the increasing of the attractive Hubbard interaction $U$ at the mean field level. This type of $SC$ phase transition is different from the traditional $SC$ phase transition which develops from the gapless Fermi Liquid. Cooperon-type gapped excitations exist in the $TI$ side near this type of $SC$ phase transition.

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Chun-Li Zang, Jing He, Ya-Jie Wu. 2015-04-09. Effects of Attractive correlation on Topological Flat-bands Model. https://arxiv.org/abs/1504.02296

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