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arXiv · 1009.6010

Phase Separation and Chemical Inhomogeneity in the Iron Chalcogenide Superconductor Fe1+yTexSe1-x

Hefei Hu·J. M. Zuo·J. S. Wen·Z. J. Xu·Z. W. Lin·Q. Li·Genda Gu·W. K. Park·L. H. Greene
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Abstract

We report investigation on Fe1+yTexSe1-x single crystals by using scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS). Both nonsuperconducting samples with excess iron and superconducting samples demonstrate nanoscale phase separation and chemical inhomogeneity of Te/Se content, which we attribute to a miscibility gap. The line scan EELS technique indicates ~20% or less fluctuation of Te concentration from the nominal compositions.

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Hefei Hu, J. M. Zuo, J. S. Wen, Z. J. Xu, Z. W. Lin, Q. Li, Genda Gu, W. K. Park, L. H. Greene. 2010-09-29. Phase Separation and Chemical Inhomogeneity in the Iron Chalcogenide Superconductor Fe1+yTexSe1-x. https://doi.org/10.1088/1367-2630/13/5/053031

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