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The Hall effect and hole densities in high Tc GaMnAs thin films

K. W. Edmonds·K. Y. Wang·R. P. Campion·A. C. Neumann·C. T. Foxon·B. L. Gallagher·P. C. Main
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Abstract

By studying the Hall effect in a series of low resistivity Ga1-xMnxAs samples, accurate values for the hole density p, Mn concentration x, and Curie temperature Tc are obtained over the range 0.015=<x=<0.08. The hole density corresponds to 90% of the Mn concentration at low x, and has a maximum value of 1.0x10-27 m-3 when Tc=125K for x=0.06. This data allows the first meaningful comparison of mean field predicted Curie temperatures with experiment over a wide range of x. The theory is in qualitative agreement with experiment, but overestimates Tc at large x and underestimates TC at low x.

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K. W. Edmonds, K. Y. Wang, R. P. Campion, A. C. Neumann, C. T. Foxon, B. L. Gallagher, P. C. Main. 2002-08-23. The Hall effect and hole densities in high Tc GaMnAs thin films. https://arxiv.org/abs/cond-mat/0205517

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