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arXiv · 1001.3909

Curie temperature versus hole concentration in field-effect structures of Ga1-xMnxAs

Y. Nishitani·D. Chiba·M. Endo·M. Sawicki·F. Matsukura·T. Dietl·H. Ohno
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Abstract

The Curie temperature TC is investigated as a function of the hole concentration p in thin films of ferromagnetic semiconductor (Ga,Mn)As. The magnetic properties are probed by transport measurements and p is varied by the application of an external electric field in a field-effect transistor configuration. It is found that TC is proportional to p^γ, where the exponent γ= 0.19 \pm 0.02 over a wide range of Mn compositions and channel thicknesses. The magnitude of gamma is reproduced by a p-d Zener model taking into account nonuniform hole distribution along the growth direction, determined by interface states and the applied gate electric fields.

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Y. Nishitani, D. Chiba, M. Endo, M. Sawicki, F. Matsukura, T. Dietl, H. Ohno. 2010-01-22. Curie temperature versus hole concentration in field-effect structures of Ga1-xMnxAs. https://doi.org/10.1103/physrevb.81.045208

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