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kappa-(BEDT-TTF)_2Cu[N(CN)_2]Br: a Fully Gapped Strong-Coupling Superconductor

H. Elsinger·J. Wosnitza·S. Wanka·J. Hagel·D. Schweitzer·W. Strunz
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Abstract

High-resolution specific-heat measurements of the organic superconductor kappa-(BEDT-TTF)_2Cu[N(CN)_2]Br in the superconducting (B = 0) and normal (B = 14 T) state show a clearly resolvable anomaly at Tc = 11.5 K and an electronic contribution, Ces, which can be reasonably well described by strong-coupling BCS theory. Most importantly, Ces vanishes exponentially in the superconducting state which gives evidence for a fully gapped order parameter.

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H. Elsinger, J. Wosnitza, S. Wanka, J. Hagel, D. Schweitzer, W. Strunz. 1999-12-02. kappa-(BEDT-TTF)_2Cu[N(CN)_2]Br: a Fully Gapped Strong-Coupling Superconductor. https://doi.org/10.1103/physrevlett.84.6098

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