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arXiv · 1809.01297

Composition-induced structural instability and strong-coupling superconductivity in Au1-xPdxTe2

Kazutaka Kudo·Hiroyuki Ishii·Minoru Nohara
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Abstract

The physical properties and structural evolution of the MX$_2$-type solid solution Au$_{1-x}$Pd$_x$Te$_2$ are reported. The end member AuTe$_2$ is a normal metal with a monoclinic distorted CdI$_2$-type structure with preformed Te-Te dimers. A monoclinic--trigonal structural phase transition at a finite temperature occurs upon Pd substitution and is suppressed to zero temperature near $x$ = 0.55, and a superconducting phase with a maximum $T_{\rm c}$ = 4.65 K emerges. A clear indication of strong coupling superconductivity is observed near the composition of the structural instability. The competitive relationship between Te-Te dimers and superconductivity is proposed.

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Kazutaka Kudo, Hiroyuki Ishii, Minoru Nohara. 2018-09-05. Composition-induced structural instability and strong-coupling superconductivity in Au1-xPdxTe2. https://doi.org/10.1103/physrevb.93.140505

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