Enhanced spin relaxation in an ultrathin metal film by the Rashba-type surface

We measured the magnetoconductance of bare and SQRT(3)×SQRT(3)-Bi/Ag-terminated ultrathin Ag(111) films by the micro-four-point probe method as a function of the applied magnetic field. The experimental curves were analyzed by introducing the results of photoemission investigation and band-structure calculations into the Hikami-Larkin-Nagaoka formula, in order to derive the characteristic fields of the two systems. The formation of the Rashba-type surface alloy was found to reduce the spin-relaxation time in the ultrathin film significantly.