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arXiv · 1403.8005

Strain effects on electronic structure and superconductivity in the iron telluride

Abstract

The influence of tensile strain in the ab-plane on crystal and electronic structure of FeTe has been studied ab initio. In superconducting FeSe the Fermi surface nesting with a vector q~(0.5,0.5)(2π/a) is believed to be crucial for rising superconductivity mediated by spin-fluctuations. The results presented here indicate that tensile-strained FeTe also exhibits such conditions. Furthermore, the Fermi surface changes, related to the increase of the lattice parameter a of this telluride, are opposite to analogous effects reported for FeSe. Since a recently reported transition from the double-stripe to the single-stripe magnetic order in FeTe under tensile strain in the ab-plane is associated with an occurence of superconductivity in corresponding thin films, these findings allow for drawing a consistent picture of superconductivity in FeSe(1-x)Te(x) systems, in general.

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M. J. Winiarski, M. Samsel-Czekała, A. Ciechan. 2014-04-14. Strain effects on electronic structure and superconductivity in the iron telluride. https://arxiv.org/abs/1403.8005

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