Field-emission of spin-polarized electrons from Cr thin film grown on W{113} surfaces

Spin polarization of field-emitted electrons from a Cr thin film grown on W{113 facets after annealing at 1000 K was measured at room temperature. The magnitude of spin polarization of 30% was two thirds of that of a Cr(001) surface, which corresponds to a fraction of the number of atoms with majority spin in Cr(001) layers. On the other hand, the emission current from Cr/W{113 was comparable to conventional field emitters so that figure of merit for spin polarized electron sources was two orders of magnitude higher than that for the Cr/W(001) emitter in previous strudy.