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arXiv · 1008.0012

Evidence of local structural inhomogeneity in FeSe(1-x)Te(x) from extended x-ray absorption fine structure

B. Joseph·A. Iadecola·A. Puri·L. Simonelli·Y. Mizuguchi·Y. Takano·N. L. Saini
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Abstract

Local structure of FeSe(1-x)Te(x) has been studied by extended x-ray absorption fine-structure (EXAFS) measurements as a function of temperature. Combination of Se and Fe K edge EXAFS has permitted to quantify the local interatomic distances and their mean-square relative displacements. The Fe-Se and Fe-Te bond lengths in the ternary system are found to be very different from the average crystallographic Fe-Se/Te distance, and almost identical to the Fe-Se and Fe-Te distances for the binary FeSe and FeTe systems, indicating distinct site occupation by the Se and Te atoms. The results provide a clear evidence of local inhomogeneities and coexisting electronic components in the FeSe1-xTex, characterized by different local structural configurations, with direct implication on the fundamental electronic structure of these superconductors.

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B. Joseph, A. Iadecola, A. Puri, L. Simonelli, Y. Mizuguchi, Y. Takano, N. L. Saini. 2010-07-30. Evidence of local structural inhomogeneity in FeSe(1-x)Te(x) from extended x-ray absorption fine structure. https://doi.org/10.1103/physrevb.82.020502

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