  The magnetization kinetics in (Zn,Mn)Se/(Zn,Be)Se quantum wells has been
studied on a ps-time scale after pulsed laser excitation. The magnetization
induced by an external magnetic field is reduced by up to 30% during ~100 ps
due to spin and energy transfer from photocarriers to Mn spin system. The giant
Zeeman splitting leads to a complete spin polarization of the carriers,
resulting in a strong suppression of flip-flop processes between carriers and
magnetic ions. Therefore a multiple angular momentum transfer from each
spin-polarized hole to the Mn ions becomes the dominant mechanism in the
magnetization dynamics. A model based on spin-momentum coupling in the valence
band is suggested for explaining this transfer.
