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Dependence of Curie Temperature on the Thickness of Epitaxial (Ga,Mn)As Film

B. S. Sorensen·J. sadowski·S. E. Andresen·P. E. Lindelof
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Abstract

We present the magnetotransport properties of very thin (5 to 15 nm) single (Ga,Mn)As layers grown by low temperature molecular beam epitaxy. A lower (Ga,Mn)As thickness limit of 5 nm for the ferromagnetic phase and the dependence of the Curie temperature on (Ga,Mn)As thickness are determined from electrical transport measurements. The Curie temperature is determined to be 97 K for the thinnest ferromagnetic sample and is found to decrease for increasing layer thickness. A carrier density of ~7.1$\times10^{20}$ cm$^{-3}$ for the 5 nm thick (Ga,Mn)As layer is determined from Hall measurements. Differences between magnetotransport properties of thick and thin (Ga,Mn)As layers are observed and discussed.

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B. S. Sorensen, J. sadowski, S. E. Andresen, P. E. Lindelof. 2002-10-22. Dependence of Curie Temperature on the Thickness of Epitaxial (Ga,Mn)As Film. https://doi.org/10.1103/physrevb.66.233313

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