In-plane and out-of-plane superfluid density of the layered organic superconductor kappa-(BEDT-TTF)(2)Cu[N(CN)(2)]Br

The anisotropic magnetic penetration depth lambda(b)(t) and lambda(ac)(t), where t = T/T-c, in the layered organic superconductor kappa-(BEDT-TTF)(2)C u[N(CN)(2)]Br (abbreviated as kappa-ET-Br) are obtained from AC susceptibil ity data. We find lambda(b)(0) = 133 mu m, consistent with earlier results and Delta lambda(b)(t) = lambda(b)(t) - lambda(b)(t) - lambda(b)(0) proport ional to t(2), which is new. Also, assuming lambda(ac)(0) approximate to 1 mu m, we obtain Delta lambda(ac)(t) proportional to t. The observed power l aws are consistent with the ones expected in d-wave superconductivity.