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arXiv · 0905.3691

Interlayer and interfacial exchange coupling in ferromagnetic metal/semiconductor heterostructures

M. J. Wilson·M. Zhu·R. C. Myers·D. D. Awschalom·P. Schiffer·N. Samarth
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Abstract

We describe a systematic study of the exchange coupling between a magnetically hard metallic ferromagnet (MnAs) and a magnetically soft ferromagnetic semiconductor (GaMnAs) in bilayer and trilayer heterostructures. An exchange spring model of MnAs/GaMnAs bilayers accounts for the variation of the exchange bias field with layer thickness and composition. We also present evidence for hole-mediated interlayer exchange coupling in MnAs/p-GaAs/\GaMnAs trilayers and study the dependence of the exchange bias field on the thickness of the spacer layer.

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M. J. Wilson, M. Zhu, R. C. Myers, D. D. Awschalom, P. Schiffer, N. Samarth. 2009-10-28. Interlayer and interfacial exchange coupling in ferromagnetic metal/semiconductor heterostructures. https://doi.org/10.1103/physrevb.81.045319

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