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Control of Coercivities in (Ga,Mn)As Thin Films by Small Concentrations of MnAs Nanoclusters

K. Y. Wang·M. Sawicki·K. W. Edmonds·R. P. Campion·A. W. Rushforth·A. A. Freeman·C. T. Foxon·B. L. Gallagher·T. Dietl
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Abstract

We demonstrate that low concentrations of a secondary magnetic phase in (Ga,Mn)As thin films can enhance the coercivity by factors up to ~100 without significantly degrading the Curie temperature or saturation magnetisation. Magnetic measurements indicate that the secondary phase consists of MnAs nanoclusters, of average size ~7nm. This approach to controlling the coercivity while maintaining high Curie temperature, may be important for realizing ferromagnetic semiconductor based devices.

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K. Y. Wang, M. Sawicki, K. W. Edmonds, R. P. Campion, A. W. Rushforth, A. A. Freeman, C. T. Foxon, B. L. Gallagher, T. Dietl. 2005-12-15. Control of Coercivities in (Ga,Mn)As Thin Films by Small Concentrations of MnAs Nanoclusters. https://doi.org/10.1063/1.2162856

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