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arXiv · 1805.10280

Pairing Mechanism in Hunds Metal Superconductors and the Universality of the Superconducting Gap to Critical Temperature Ratio

Tsung-Han Lee·Andrey Chubukov·Hu Miao·Gabriel Kotliar
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Abstract

We analyze a simple model containing the physical ingredients of a Hund's metal, the local spin fluctuations with power-law correlators, $(\Omega_0/|\Omega|)^\gamma$, with $\gamma$ greater than one, interacting with electronic quasiparticles. While the critical temperature and the gap change significantly with varying parameters, the $2\Delta_{max}/k_BT_c$ remains close to twice the BCS value in agreement with experimental observations in the iron-based superconductors (FeSC).

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Tsung-Han Lee, Andrey Chubukov, Hu Miao, Gabriel Kotliar. 2018-05-25. Pairing Mechanism in Hunds Metal Superconductors and the Universality of the Superconducting Gap to Critical Temperature Ratio. https://doi.org/10.1103/physrevlett.121.187003

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