Reduction of the Ni(110) surface spin- and orbital-magnetic moment by a c(2 X 2) S overlayer - art. no. 064407

The modification of the room-temperature surface magnetic moment of Ni(110) by a c(2x2)S overlayer has been investigated using spin-polarized inverse photoemission (SPIPE) and magnetic circular dichroism (MCD) in core-level p hotoemission. SPIPE measurements, which are mostly sensitive to the spin co ntribution, indicate a reduction of the spin polarization to (44+/-19)% of the clean surface value. The MCD, which is mostly sensitive to the orbital moment, is reduced to (25 +/- 3) %. This apparent difference in the sensiti vity to the S overlayer can in part be explained by considering the differe nt sampling depths of the two techniques. The results provide support for t heoretical predictions that the clean surface magnetic moment of Ni(110), i n both the spin and orbital contributions, is enhanced compared to the bulk .