We have investigated experimentally the spin transport properties in ferromagnetic–superconductor–ferromagnetic double-barrier tunnel junctions. The transport measurements were conducted at mK temperatures with magnetic fields applied along the leads. When the magnetic moments of the two ferromagnetic leads were in opposite orientations (i.e. antiferromagnetic alignment), majority of the spins accumulated in the superconducting island. This was evidenced by a suppression of the superconducting gap.
Journal of Magnetism and Magnetic Materials, 239(1-3): 141-144