Phase control of κ-(BEDT-TTF)2Cu[N(CN)2]Br by partial deuteration

Abstract κ-(BEDT-TTF) 2 X system is well known as the strong correlated electron system with the phase boundary of the superconducting and the antiferromagnetic ordering phases. We controlled the boundary with the partial deuterization technique on κ-(BEDT-TTF) 2 Cu[N(CN) 2 ]Br and found the boundary was sensitive to cooling rate around at 80 K, at which the lattice anomaly occurred. We also found the external magnetic field dependence of the boundary.