We report on the spin-polarized photoreflectance in a ferromagnetic
GaMnAs layer. The transient photoreflectance results show a circular
polarization dependence of the probe beam in quasi-degenerate
pump-probe measurements. The circular polarization d...
We report on the spin-polarized photoreflectance in a ferromagnetic
GaMnAs layer. The transient photoreflectance results show a circular
polarization dependence of the probe beam in quasi-degenerate
pump-probe measurements. The circular polarization dependence, which
follows the magnetization as we increase the sample temperature, can
be understood from the strong spin exchange coupling between
conduction or valence band electrons and localized Mn ion spins.