Competition between magnetism and superconductivity in the organic metal $\kappa$-[BEDT-TTF]${}_2$Cu[N(CN)${}_2$]Br

David Fournier, Mario Poirier, Kim Doan Truong

Ultrasonic velocity and attenuation measurements on the quasi-two-dimensional organic conductor $\kappa$-[BEDT-TTF]${}_2$Cu[N(CN)${}_2$]Br give the first determination of the coexistence zo…