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arXiv · 1012.1678

Tailoring the magnetism of GaMnAs films by ion irradiation

Lin Li·S. D. Yao·Shengqiang Zhou·D. Bürger·O. Roshchupkina·S. Akhmadaliev·A. W. Rushforth·R. P. Campion·J. Fassbender·M. Helm·B. L. Gallagher·C. Timm·H. Schmidt
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Abstract

Ion irradiation of semiconductors is a well understood method to tune the carrier concentration in a controlled manner. We show that the ferromagnetism in GaMnAs films, known to be hole-mediated, can be modified by He ion irradiation. The coercivity can be increased by more than three times. The magnetization, Curie temperature and the saturation field along the out-of-plane hard axis all decrease as the fluence increases. The electrical and structural characterization of the irradiated GaMnAs layers indicates that the controlled tailoring of magnetism results from a compensation of holes by generated electrical defects.

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Lin Li, S. D. Yao, Shengqiang Zhou, D. Bürger, O. Roshchupkina, S. Akhmadaliev, A. W. Rushforth, R. P. Campion, J. Fassbender, M. Helm, B. L. Gallagher, C. Timm, H. Schmidt. 2010-12-08. Tailoring the magnetism of GaMnAs films by ion irradiation. https://doi.org/10.1088/0022-3727/44/4/045001

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