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arXiv · 2302.07790

Superconducting ground state study of valence skip compound AgSnSe$_2$

A. Kataria·Arushi·S. Sharma·T. Agarwal·M. Pula·J. Beare·S. Yoon·Y. Cai·K. M. Kojima·G. M. Luke·R. P. Singh
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Abstract

The valence-skipped superconductors are natural candidates for unconventional superconductivity, as they can exhibit a negative effective, attractive interaction for electron-pairing. This work reports comprehensive XRD, magnetization, specific heat and muon spin rotation and relaxation measurements ($\mu$SR) on a valence-skipped compound: AgSnSe$_2$. The temperature dependence of the electronic specific heat ($C_{el}(T)$) and of the upper critical field ($H_{c2}(T)$) provide evidence of two-gap superconductivity, which is also confirmed by our transverse-field $\mu$SR measurements. Our zero-field $\mu$SR measurements suggest preserved time-reversal symmetry in the superconducting ground state of AgSnSe$_2$.

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A. Kataria, Arushi, S. Sharma, T. Agarwal, M. Pula, J. Beare, S. Yoon, Y. Cai, K. M. Kojima, G. M. Luke, R. P. Singh. 2023-02-15. Superconducting ground state study of valence skip compound AgSnSe$_2$. https://doi.org/10.1103/physrevb.107.174517

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