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Confinement engineering of s-d exchange interactions in GaMnAs quantum wells

N. P. Stern·R. C. Myers·M. Poggio·A. C. Gossard·D. D. Awschalom
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Abstract

Recent measurements of coherent electron spin dynamics reveal an antiferromagnetic s-d exchange coupling between conduction band electrons and electrons localized on Mn{2+} impurities in GaMnAs quantum wells. Here we discuss systematic measurements of the s-d exchange interaction in GaMnAs/AlGaAs quantum wells with different confinement potentials using time-resolved Kerr rotation. Extending previous investigations of the dependence of the s-d exchange, N{0}alpha, on well width, we find that its magnitude also depends on well depth. Both phenomena reduce to a general dependence on confinement energy, described by a band-mixing model of confinement-induced kinetic exchange in the conduction band.

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N. P. Stern, R. C. Myers, M. Poggio, A. C. Gossard, D. D. Awschalom. 2006-04-25. Confinement engineering of s-d exchange interactions in GaMnAs quantum wells. https://doi.org/10.1103/physrevb.75.045329

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