Superconducting state in the layered organic superconductor κ-(BEDT-TTF)2Cu[N(CN)2]Br

We summarize the main features of the magnetic field-temperature phase diagram for the superconducting state of κ-(BEDTTTF) 2Cu[N(CN)2]Br. The initial temperature dependence of the real component of ac susceptibility for field parallel and perpendicular to the ac plane are markedly different. The out-of-plane penetration depth λb and the related superfluid density vary at low tempeartures as T1. Slow flux dynamics below the irreversibility line for the ac field perpendicular to the BEDT-TTF planes might be ascribed to a vortex-pair creation process. The characteristic relaxation time τ >10−4 s is thermally activated with an activation energy of about 300K.