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arXiv · 1308.2933

Strain effects on electronic structure of the iron selenide superconductor

M. J. Winiarski·M. Samsel-Czekała·A. Ciechan
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Abstract

The influence of various strains on crystal and electronic structures of superconducting FeSe has been studied ab initio. We consider changes in the Fermi surface nesting with a vector Q=(0.5,0.5)*(2π/a) as crucial for rising superconductivity (SC) mediated by spin-fluctuations (SF). Our results indicate that the c-axis strained FeSe exhibits the most imperfect nesting, which enhances SF and, hence, also SC. In turn, the ab-plane compressive strain slightly weakens this} nesting while the tensile strain destroys it completely. These findings are consistent with reported earlier experimental dependencies of superconducting transition temperatures on strain in FeSe thin films.

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M. J. Winiarski, M. Samsel-Czekała, A. Ciechan. 2013-08-13. Strain effects on electronic structure of the iron selenide superconductor. https://doi.org/10.1209/0295-5075%2F100%2F47005

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