2010/07/30 by B. Joseph, A. Iadecola, A. Puri +4
Physics and Astronomy · #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.82.020502
published as Physical Review B 82, 020502(R) (2010) · http://link.aps.org/doi/10.1103/PhysRevB.82.020502
arxiv created 2010/07/30 · arxiv updated 2010/08/03
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.