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arXiv · 1001.2449

Exchange bias of a ferromagnetic semiconductor by a ferromagnetic metal

K. Olejnik·P. Wadley·J. A Haigh·K. W. Edmonds·R. P. Campion·A. W. Rushforth·B. L. Gallagher·C. T. Foxon·T. Jungwirth·J. Wunderlich·S. S. Dhesi·S. Cavill·G. van der Laan·E Arenholz
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Abstract

We demonstrate an exchange bias in (Ga,Mn)As induced by antiferromagnetic coupling to a thin overlayer of Fe. Bias fields of up to 240 Oe are observed. Using element-specific x-ray magnetic circular dichroism measurements, we distinguish a strongly exchange coupled (Ga,Mn)As interface layer in addition to the biassed bulk of the (Ga,Mn)As film. The interface layer remains polarized at room temperature.

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K. Olejnik, P. Wadley, J. A Haigh, K. W. Edmonds, R. P. Campion, A. W. Rushforth, B. L. Gallagher, C. T. Foxon, T. Jungwirth, J. Wunderlich, S. S. Dhesi, S. Cavill, G. van der Laan, E Arenholz. 2010-01-14. Exchange bias of a ferromagnetic semiconductor by a ferromagnetic metal. https://doi.org/10.1103/physrevb.81.104402

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