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arXiv · 1709.08899

SnAs-based layered superconductor NaSn2As2

Yosuke Goto·Akira Yamada·Tatsuma D. Matsuda·Yuji Aoki·Yoshikazu Mizuguchi
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Abstract

Superconductivity with exotic properties has often been discovered in materials with a layered (two-dimensional) crystal structure. The low dimensionality affects the electronic structure of materials, which could realize a high transition temperature (Tc) and/or unconventional pairing mechanisms. Here, we report the superconductivity in a layered tin arsenide NaSn2As2. The crystal structure consists of (Sn2As2)2- bilayers, which is bound by van-der-Waals forces, separated by Na+ ions. Measurements of electrical resistivity and specific heat confirm the bulk nature of superconductivity of NaSn2As2 with Tc of 1.3 K. Our results propose that the SnAs layers will be a basic structure providing another universality class of a layered superconducting family, and it provides a new platform for the physics and chemistry of low-dimensional superconductors with lone pair electrons.

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Yosuke Goto, Akira Yamada, Tatsuma D. Matsuda, Yuji Aoki, Yoshikazu Mizuguchi. 2017-09-26. SnAs-based layered superconductor NaSn2As2. https://doi.org/10.7566/jpsj.86.123701

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