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arXiv · 2111.11319

Superconductivity in layered Zintl phase LiSn2As2

Junjie Wang·Xiangru Cui·Yimin Wan·Tianping Ying·Shiyan Li·Jiangang Guo
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Abstract

We report the superconductivity in the layered Zintl phase LiSn$_2$As$_2$, which is isostructural to NaSn$_2$As$_2$ and has a transition temperature ($T_{\mathrm{c}}$) of 1.6 K. Despite similar $T_{\mathrm{c}}$ and Debye temperatures, substituting of Na with Li considerably increases the upper critical field. Based on a systematically comparation of Sn$_4$As$_3$, NaSnAs, NaSn$_2$As$_2$,Na$_{1-x}$Sn$_2$P$_2$, SrSn$_2$As$_2$, and LiSn$_2$As$_2$, we propose that carrier doping, intimately related to the formation of lone-pair electrons, controls superconductivity in layered SnAs-based compounds rather than chemical pressure. The current findings provide a thorough and comprehensive understanding of Sn-based Zintl phase.

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Junjie Wang, Xiangru Cui, Yimin Wan, Tianping Ying, Shiyan Li, Jiangang Guo. 2021-11-22. Superconductivity in layered Zintl phase LiSn2As2. https://arxiv.org/abs/2111.11319

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