Spin injection device having a shared superconductor electrode

摘要

A spin injection device (1) characterized in that it comprises a first and a second tunnel junctions (2, 3) which have a common electrode composed of a superconductor (4') and each of which has a counterelectrode composed of a first or a second ferromagnet (6, 7), wherein: said first and second tunnel junctions (2, 3) are disposed spaced apart from each other by a distance that is shorter than a spin diffusion length of said superconductor (4'); said first tunnel junction (2) is a tunnel junction for spin injection therein from said first ferromagnetic metal (6) into said superconductor (4'); and said second tunnel junction (3) is a tunnel junction for detection between said second ferromagnetic metal (7) and said superconductor (4') therein of a voltage accompanying the spin injection.