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arXiv · 2103.07249

K2Mo3As3 is a Multi-Gap Electron-Phonon Superconductor

Bing-Hua Lei·David J. Singh
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Abstract

We show using density functional calculations that quasi-one-dimensional K2Mo3As3, which is closely related to the K2Cr3As3 and has very similar superconducting properties, is not close to magnetism and has conventional s-wave electron-phonon superconductivity. This superconductivity is of multi-gap character due to different coupling on different Fermi surface sheets. This is discussed in relation to the properties of this family of quasi-one-dimensional pnictide superconductors. The results show that this family of superconductors provides a unique opportunity for studying the interplay of spin-fluctuations and electron-phonon superconductivity in transition metal pnictides and offer a path for sorting out the different proposed superconducting scenarios in this fascinating family of pnictide superconductors.

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Bing-Hua Lei, David J. Singh. 2021-03-12. K2Mo3As3 is a Multi-Gap Electron-Phonon Superconductor. https://doi.org/10.1103/physrevb.103.094512

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