Spin-dependent transmission of low-energy electrons through ultrathin magnetic layers.

Abstract

We present an experiment in which the attenuation of a spin-polarized free electron beam is measured by direct transmission through an ultrathin ferromagnetic layer. The self-supported metal target consists of a 1-nm-thick cobalt film sandwiched between 21- and 2-nm-thick gold layers. Measurements are performed throughout a wide energy range (incident electron energies from 4 eV to 50 eV above the Fermi level). At low energy, close to the clean surface vacuum level, we find that the transmission coefficient of minority spin electrons is about 0.7 times that of majority spin electrons.