Variation of transition temperatures and residual resistivity ratio in vapor-grown FeSe

A. E. Böhmer; V. Taufour; W. E. Straszheim; T. Wolf; P. C. Canfield

doi:10.1103/physrevb.94.024526

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arXiv · 1606.00500

Variation of transition temperatures and residual resistivity ratio in vapor-grown FeSe

A. E. Böhmer·V. Taufour·W. E. Straszheim·T. Wolf·P. C. Canfield

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Abstract

The study of the iron-based superconductor FeSe has blossomed with the availability of high quality single crystals, obtained through flux/vapor-transport growth techniques below the structural transformation temperature of its tetragonal phase, T~450 C. Here, we report on the variation of sample morphology and properties due to small modifications in the growth conditions. A considerable variation of the superconducting transition temperature Tc, from 8.8 K to 3 K, which cannot be correlated with the sample composition, is observed. Instead, we point out a clear correlation between Tc and disorder, as measured by the residual resistivity ratio. Notably, the tetragonal-to-orthorhombic structural transition is also found to be quite strongly disorder dependent (Ts =72 - 90 K), and linearly correlated with Tc.

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A. E. Böhmer, V. Taufour, W. E. Straszheim, T. Wolf, P. C. Canfield. 2016-06-01. Variation of transition temperatures and residual resistivity ratio in vapor-grown FeSe. https://doi.org/10.1103/physrevb.94.024526

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