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arXiv · 0801.2502

Superconductor-Insulator Phase Separation Induced by Rapid Cooling in kappa-(ET)_2Cu[N(CN)_2]Br

O. J. Taylor·A. Carrington·J. A. Schlueter
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Abstract

We present measurements of the low temperature specific heat of single crystals of kappa-(ET)_2Cu[N(CN)_2]Br as a function of the cooling rate through the glasslike structure transition at $\sim$ 80K. We find that rapid cooling produces a small (< 4%) decrease in the superconducting transition temperature accompanied by a substantial (up to 50%) decrease in the normal-state electronic specific heat. A natural explanation of our data is that there is a macroscopic phase separation between superconducting and insulating regions in rapidly cooled samples.

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O. J. Taylor, A. Carrington, J. A. Schlueter. 2008-01-16. Superconductor-Insulator Phase Separation Induced by Rapid Cooling in kappa-(ET)_2Cu[N(CN)_2]Br. https://doi.org/10.1103/physrevb.77.060503

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