Theory of superconductivity in SrPtAs

Wan-Sheng Wang; Yang Yang; Qiang-Hua Wang

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arXiv · 1312.3071

Theory of superconductivity in SrPtAs

Wan-Sheng Wang·Yang Yang·Qiang-Hua Wang

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Abstract

We constructed tight-binding models for the new superconductor SrPtAs according to first principle calculations, and by functional renormalization group we investigated the effect of electron correlations and spin-orbital coupling (SOC) in Cooper pairing. We found that out of the five $d$-orbitals, the $(xz,yz)$-orbitals are the active ones responsible for superconductivity, and ferromagnetic fluctuations enhanced by the proximity to the van Hove singularity triggers $f$-wave triplet pairing. The superconducting transition temperature increases as the Fermi level is closer to the van Hove singularity until ferromagnetism sets in. The $d$-vector of the triplet pairing component is pinned by SOC along the out-of-plane direction. Experimental perspectives are discussed.

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Wan-Sheng Wang, Yang Yang, Qiang-Hua Wang. 2013-12-11. Theory of superconductivity in SrPtAs. https://arxiv.org/abs/1312.3071

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