Portal de Periódicos da CAPES

Fundamental obstacle for electrical spin injection from a ferromagnetic metal into a diffusive semiconductor

2000; American Physical Society; Volume: 62; Issue: 8 Linguagem: Inglês

10.1103/physrevb.62.r4790

1095-3795

G. Schmidt, D. Ferrand, L. W. Molenkamp, A. T. Filip, B. J. van Wees,

Physics of Superconductivity and Magnetism

We have calculated the spin-polarization effects of a current in a two-dimensional electron gas which is contacted by two ferromagnetic metals. In the purely diffusive regime, the current may indeed be spin-polarized. However, for a typical device geometry the degree of spin-polarization of the current is limited to less than 0.1% only. The change in device resistance for parallel and antiparallel magnetization of the contacts is up to quadratically smaller, and will thus be difficult to detect.