FEASIBILITY OF MEASURING SURFACE ELECTRON-SPIN DYNAMICS BY INELASTIC-SCATTERING OF METASTABLE HELIUM-ATOMS

The application of inelastic scattering of monoenergetic beams of meta stable 2(3)S helium atoms (He) from surfaces of magnetic insulators t o study the dynamical properties of surface electron-spin systems is c onsidered. The study is based on a calculation of the differential ine lastic reflection coefficient for magnetic scattering using a distorte d-wave Born approximation approach. The NiO(001) surface is used as an example. The adiabatic scattering potential as well as the exchange c oupling between a metastable He atom and the surface electron spins ar e determined by a configuration interaction calculation for an embedde d NiO cluster model. The efficiency of measuring an inelastic magnetic event based on this calculation is estimated to be similar to 10(-6).