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Magnetic Properties of Short Period InGaMnAs/InGaAs Superlattices

J. Sadowski·R. Mathieu·P. Svedlindh·J. Kanski·M. Karlsteen·K. Swiatek·J. Z. Domagala
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Abstract

We have observed a paramagnetic-to-ferromagnetic phase transition in short period InGaMnAs/InGaAs superlattices. The thicknesses of magnetic InGaMnAs layers in the structures studied was chosen to be 4 or 8 molecular layers (12 Åor 24 Å). The nonmagnetic InGaAs spacer layers are 12 Åthick. The In content of InGaMnAs and InGaAs layers was chosen in such a way that magnetic layers were: deep potential wells, high potential barriers or shallow potential wells. For superlattices with 8 monolayer thick InGaMnAs magnetic layers and 4 monolayer thick InGaAs nonmagnetic spacers the temperatures of paramagnetic-to-ferromagnetic phase transition do not depend on the band offsets between InGaMnAs and InGaAs adjusted by the In content.

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J. Sadowski, R. Mathieu, P. Svedlindh, J. Kanski, M. Karlsteen, K. Swiatek, J. Z. Domagala. 2002-07-09. Magnetic Properties of Short Period InGaMnAs/InGaAs Superlattices. https://arxiv.org/abs/cond-mat/0207232

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