A study of the electronic structure ofFeSe1 − xTex chalcogenides by Fe and Se K-edge x-ray absorption near edge structure measurements

Abstract

Fe K-edge and Se K-edge x-ray absorption near edge structure (XANES) measurements are used to studythe FeSe1 − xTex electronic structure of chalcogenides. An intense Fe K-edge pre-edge peak due to Fe (and admixed Se/Te p states) is observed, showing substantial change with Te substitutionand x-ray polarization. The main white line peak in the Se K-edge XANES due to Se transition appears similar to the one expected forSe2 − systems and changes with Te substitution. Polarization dependencereveals that unoccupied Se orbitals near the Fermi level have predominantpx, y character. The results provide key information on the hybridization of Fe 3d and chalcogenp states in the Fe-based chalcogenide superconductors.