A method and system for providing a spin filter is disclosed. The method
and system include providing a pinned layer, a free layer, and a
conductive nonmagnetic spacer layer between the pinned layer and the free
layer. The method and system also include providing a spin filter layer
and a capping layer on the spin filter layer. The spin filter layer is
adjacent to the free layer. The spin filter layer is on an opposite side
of the free layer as the nonmagnetic spacer layer and includes at least
Pt and/or Rh. The capping layer has a specular reflection layer therein.
In one aspect, the specular reflection layer allows specular reflection
of current carriers traveling from the spin filter layer to the specular
reflection layer. In another aspect, the specular reflection layer
includes at least Ta, Ti, Zr, Hf, Nb, Al, Mo, W, Si, Cr, V, Ni, Co, and
Fe.