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Multiple transfer of angular momentum quanta from a spin-polarized hole to magnetic ions in ZnMnSe/ZnBeSe quantum wells

A. V. Akimov·A. V. Scherbakov·D. R. Yakovlev·I. A. Merkulov·M. Bayer·A. Waag·L. W. Molenkamp
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Abstract

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.

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A. V. Akimov, A. V. Scherbakov, D. R. Yakovlev, I. A. Merkulov, M. Bayer, A. Waag, L. W. Molenkamp. 2006-01-30. Multiple transfer of angular momentum quanta from a spin-polarized hole to magnetic ions in ZnMnSe/ZnBeSe quantum wells. https://doi.org/10.1103/physrevb.73.165328

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