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arXiv · 0803.3245

Stoichiometric growth of high Curie temperature heavily-alloyed GaMnAs

S. Mack·R. C. Myers·J. T. Heron·A. C. Gossard·D. D. Awschalom
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Abstract

Heavily-alloyed, 100 nm Ga1-xMnxAs (x>0.1) films are obtained via low temperature molecular beam epitaxy utilizing a combinatorial technique which allows systematic control of excess arsenic during growth. Reproducible, optimized electronic, magnetic and structural properties are found in a narrow range of stoichiometric growth conditions. The Curie temperature of stoichiometric material is 150-165 K and independent of x within a large window of growth conditions while substitutional Mn content increases linearly, contradicting the prediction of the Zener Model of hole-mediated ferromagnetism.

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S. Mack, R. C. Myers, J. T. Heron, A. C. Gossard, D. D. Awschalom. 2008-03-22. Stoichiometric growth of high Curie temperature heavily-alloyed GaMnAs. https://doi.org/10.1063/1.2927481

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