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arXiv · 1002.2669

Control of tetrahedral coordination and superconductivity in FeSe0.5Te0.5 thin films

S. X. Huang·C. L. Chien·V. Thampy·C. Broholm
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Abstract

We demonstrate a close relationship between superconductivity and the dimensions of the Fe-Se(Te) tetrahedron in FeSe0.5Te0.5. This is done by exploiting thin film epitaxy, which provides controlled biaxial stress, both compressive and tensile, to distort the tetrahedron. The Se/Te height within the tetrahedron is found to be of crucial importance to superconductivity, in agreement with the theoretical proposal that (pi,pi) spin fluctuations promote superconductivity in Fe superconductors.

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S. X. Huang, C. L. Chien, V. Thampy, C. Broholm. 2010-02-13. Control of tetrahedral coordination and superconductivity in FeSe0.5Te0.5 thin films. https://doi.org/10.1103/physrevlett.104.217002

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