Abstract

Currents flowing in circuits containing ferromagnets transport spin as well as charge; this is the fundamental origin of effects such as giant magnetoresistance (GMR). In contrast, the superconducting state is created by the pairing of electrons with antiparallel spins; this means that a supercurrent transports charge but not spin. Until very recently this would have made the idea of superconducting spin electronics completely paradoxical. The possibility that the alternative triplet pairing state could be induced in ferromagnets had been theoretically predicted and convincing evidence for long-range supercurrents in ferromagnets has now been obtained by several groups, working on different materials systems. Because triplet supercurrents are expected to be spin polarised, form the starting point for a programme aiming to merge the exciting fields of superconductivity and spintronics. This talk describes the developments which have led to this point and the current research taking place within the Materials Department.