Enhanced superconducting properties in FeCr$_x$Se

Anil K Yadav; Ajay D. Thakur; C V Tomy

doi:10.1016/j.ssc.2011.01.010

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arXiv · 1011.6519

Enhanced superconducting properties in FeCr$_x$Se

Anil K Yadav·Ajay D. Thakur·C V Tomy

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Abstract

We report an enhancement of superconducting transition temperature ($T_{\rm c}$) when Chromium (Cr) is substituted in excess at the Iron (Fe) site (FeCr$_x$Se, $x=$0.01, 0.02 and 0.03). There is a corresponding increase in the superconducting volume fraction with $T_{\rm c}$ attaining a value of 11.2 K on 2 $%$ Cr substitution when compared to a $T_{\rm c}$ of 8.5 K for the conventional tetragonal Fe-excess sample Fe$_{1+x}$Se. The results point to the role of chemical pressure (introduced via ionic size variation at the Fe site upon Cr substitution in excess) on superconducting properties.

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Anil K Yadav, Ajay D. Thakur, C V Tomy. 2010-11-30. Enhanced superconducting properties in FeCr$_x$Se. https://doi.org/10.1016/j.ssc.2011.01.010

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