Highly efficient spin filtering of ballistic electrons

Abstract

Spin dependent electron transport in hybrid Au/Co/Cu/NiFe/n-GaAs spin valve Schottky barrier structures was investigated using photoexcitation at various wavelengths. For excitation with the photon energy well above the Schottky barrier height we found a ~2400% increase in helicity dependent photocurrent on switching the spin valve from parallel to antiparallel alignment. Our observations provide clear evidence for highly efficient spin filtering of spin polarized ballistic electrons.