Electron depolarization by inelastic exchange scattering fromCr3+magnetic moments

Inelastic exchange scattering of low-energy electrons off disordered localized ${\mathrm{Cr}}^{3+}$ magnetic moments at a ${\mathrm{Cr}}_2$ ${\mathrm{O}}_3$ surface is studied by spin-polarized electron-energy-loss spectroscopy. The excitations from a spin-quartet ground state to doublet states via exchange scattering give rise to sharp energy-loss lines, which are predominantly spin flip, and provide an efficient electron depolarization mechanism.