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

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.

4 pages, 4 figures

References in corpus (4)

• Similarities between organic and cuprate superconductors
• Pairing due to Spin Fluctuations in Layered Organic Superconductors
• Low Temperature Penetration depth of κ-(ET)_2Cu[N(CN)_2]Br and κ-(ET)_2Cu(NCS)_2
• Low-Field Anomaly in the Specific Heat of s-wave Superconductors due to the Expansion of the Vortex Cores

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