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arXiv · 1308.4476

Loop Current and Orbital Magnetism in Pyrite-Type $Ir_{3}Ch_{8}$ ($Ch=Se,Te$)

Xiaotian Zhang·Xianxin Wu·Di Xiao·Jiangping Hu
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Abstract

We study the parent compound of the pyrite-type $Ir_{x}Ch_{2}$ iridium chalcogenide superconductors, $Ir_{0.75}Ch_{2}$ (or $Ir_{3}Ch_{8}$). While the lattice structure of the material is rather complicated, we show that the electron physics near the Fermi surface (FS) can be described by a three-band tight-binding model. We find that the material possesses a loop current ground state which is responsible for the highly anisotropic strong diamagnetism observed in experiments. The fluctuations of this loop current state can be a possible pairing mechanism for superconductivity.

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Xiaotian Zhang, Xianxin Wu, Di Xiao, Jiangping Hu. 2013-08-21. Loop Current and Orbital Magnetism in Pyrite-Type $Ir_{3}Ch_{8}$ ($Ch=Se,Te$). https://arxiv.org/abs/1308.4476

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