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arXiv · 1012.1436

A study of electronic structure of FeSe$_{1-x}$Te$_{x}$ chalcogenides by Fe and Se K-edge x-ray absorption near edge structure measurements

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

Fe K-edge and Se K-edge x-ray absorption near edge structure (XANES) measurements are used to study FeSe$_{1-x}$Te$_{x}$ electronic structure of chalcogenides. An intense Fe K-edge pre-edge peak due to Fe 1s$\to$3d (and admixed Se/Te $p$ states) is observed, showing substantial change with the Te substitution and X-ray polarization. The main white line peak in the Se K-edge XANES due to Se 1s $\to$ 4p transition appear similar to the one expected for Se$^{2-}$ systems and changes with the Te substitution. Polarization dependence reveals that unoccupied Se orbitals near the Fermi level have predominant $p_{x,y}$ character. The results provide key information on the hybridization of Fe $3d$ and chalcogen $p$ states in the Fe-based chalcogenide superconductors.

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B. Joseph, A. Iadecola, L. Simonelli, Y. Mizuguchi, Y. Takano, T. Mizokawa, N. L. Saini. 2010-12-07. A study of electronic structure of FeSe$_{1-x}$Te$_{x}$ chalcogenides by Fe and Se K-edge x-ray absorption near edge structure measurements. https://doi.org/10.1088/0953-8984/22/48/485702

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