SPIN-POLARIZED ELECTRONS FROM INXGA1-XAS THIN-FILMS

Using optical spin orientation photoelectrons with spin polarization a bove 50% have been extracted from strained III-V semiconductors. The n ew sources consist of an epitaxial overlayer having a smaller energy g ap and a slightly larger lattice constant than the substrate material. The tensile stress along the surface normal lifts the orbital degener acy of the levels at the valence band maximum such that the polarizati on is enhanced compared to the unstrained cubic material.