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arXiv · 1805.05915

Orbital-selective superconductivity in the nematic phase of FeSe

Haoyu Hu·Rong Yu·Emilian M. Nica·Jian-Xin Zhu·Qimiao Si
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Abstract

The interplay between electronic orders and superconductivity is central to the physics of unconventional superconductors, and is particularly pronounced in the iron-based superconductors. Motivated by recent experiments on FeSe, we study the superconducting pairing in its nematic phase in a multiorbital model with frustrated spin-exchange interactions. The electron correlations in the presence of the nematic order give rise to an enhanced orbital selectivity in the superconducting pairing amplitudes. This orbital-selective pairing produces a large gap anisotropy on the Fermi surface. Our results naturally explain the striking experimental observations, and shed new light on the unconventional superconductivity of correlated electron systems in general.

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Haoyu Hu, Rong Yu, Emilian M. Nica, Jian-Xin Zhu, Qimiao Si. 2018-05-15. Orbital-selective superconductivity in the nematic phase of FeSe. https://doi.org/10.1103/physrevb.98.220503

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