Symmetry-dependent alignment of the electron-spin polarization vector due to electronic band hybridization observed in photoemission from Ag(100)

Abstract

We have performed spin- and angle-resolved photoemission experiments in normal emission from a (100) surface of silver using circularly polarized synchrotron radiation at oblique and normal incidence. The observed spin polarization reaches values up to 45%, with the corresponding peaks in the intensity distributions fully consistent with the bulk band structure. In the case of normally incident light the spin polarization vector is aligned with the surface normal, whereas deviations from this behavior are found at oblique incidence of the circularly polarized light. A particular hybridization in the initial states is responsible for this effect, which can be understood on the base of symmetry arguments.