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arXiv · 0902.1519

Bulk Superconductivity at 14 K in Single Crystals of Fe1+yTexSe1-x

B. C. Sales·A. S. Sefat·M. A. McGuire·R. Y. Jin·D. Mandrus·Y. Mozharivskyj
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Abstract

Resistivity, magnetic susceptibility and heat capacity measurements are reported for single crystals of Fe1+yTexSe1-x grown via a modified Bridgeman method with 0 < y < 0.15, and x= 1, 0.9, 0.75, 0. 67, 0.55 and 0.5. Although resistivity measurements show traces of superconductivity near 14 K for all x except x=1, only crystals grown with compositions near x=0.5 exhibit bulk superconductivity. The appearance of bulk superconductivity correlates with a reduction in the magnitude of the magnetic susceptibility at room temperature and smaller values of y, the concentration of Fe in the Fe(2) site.

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B. C. Sales, A. S. Sefat, M. A. McGuire, R. Y. Jin, D. Mandrus, Y. Mozharivskyj. 2009-02-09. Bulk Superconductivity at 14 K in Single Crystals of Fe1+yTexSe1-x. https://doi.org/10.1103/physrevb.79.094521

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