DIFFRACTION OF SPIN-POLARIZED CU 3P PHOTOELECTRONS

We measured the spin-orbit-induced spin polarization in Cu 3p photoemi ssion for fixed angle between light incidence and electron collection, while varying the emission angle relative to the crystal lattice. The polarization is found to vary strongly with emission direction in bot h sublevels. However, the ratio between the polarizations of the j = 3 /2 and j = 1/2 sublevels is close to -1/2 for all emission directions. The spin polarization and its dependence on emission direction can bo th be viewed as arising from the angular momentum character of the fin al state wave which is imposed by the excitation conditions.