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Two Dimensional Diluted Magnetic Semiconductor Systems

D. J. Priour Jr·E. H. Hwang·S. Das Sarma
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Abstract

We develop a theory for two-dimensional diluted magnetic semiconductor systems (e.g. $\textrm{Ga}_{1-x}\textrm{Mn}_{x}\textrm{As}$ layers) where the itinerant carriers mediating the ferromagnetic interaction between the impurity local moments, as well as the local moments themselves, are confined in a two-dimensional layer. The theory includes exact spatial disorder effects associated with the random local moment positions within a disordered RKKY lattice field theory description. We predict the ferromagnetic transition temperature ($T_{c}$) as well as the nature of the spontaneous magnetization. The theory includes disorder and finite carrier mean free path effects as well as the important correction arising from the {\it finite temperature} RKKY interaction, finding a strong density dependence of $T_{c}$ in contrast to the simple virtual crystal approximation.

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D. J. Priour Jr, E. H. Hwang, S. Das Sarma. 2005-05-04. Two Dimensional Diluted Magnetic Semiconductor Systems. https://doi.org/10.1103/physrevlett.95.037201

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