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Effects of annealing time on defect-controlled ferromagnetism in Ga1-xMnxAs

S. J. Potashnik·K. C. Ku·S. H. Chun·J. J. Berry·N. Samarth·P. Schiffer
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Abstract

We have studied the evolution of the magnetic, electronic, and structural properties of annealed epilayers of Ga1-xMnxAs grown by low temperature molecular beam epitaxy. Annealing at the optimal temperature of 250 C for less than 2 hours significantly enhances the conductivity and ferromagnetism, but continuing the annealing for longer times suppresses both. These data indicate that such annealing induces the defects in Ga1-xMnxAs to evolve through at least two different processes, and they point to a complex interplay between the different defects and ferromagnetism in this material.

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S. J. Potashnik, K. C. Ku, S. H. Chun, J. J. Berry, N. Samarth, P. Schiffer. 2001-05-28. Effects of annealing time on defect-controlled ferromagnetism in Ga1-xMnxAs. https://doi.org/10.1063/1.1398619

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