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arXiv · 0802.3863

A novel technique to make Ohmic contact to a buried two-dimensional electron gas in a molecular-beam-epitaxy grown $GaAs/Al_{0.3}Ga_{0.7}As$ heterostructure with Mn $δ$-doping

A. Bove·F. Altomare·N. B. Kundtz·Albert M. Chang·Y. J. Cho·X. Liu·J. Furdyna
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Abstract

We report on the growth and characterization of a new Diluted Magnetic Semiconductor (DMS) heterostructure that presents a Two-Dimensional Electron Gas (2DEG) with a carrier density $n \sim 1.08 \times 10^{12} cm^{-2}$ and a mobility $μ\sim 600 cm^{2} / (Vs)$ at T $\sim$ 4.2K. As far as we know this is the highest mobility value reported in the literature for GaMnAs systems. A novel technique was developed to make Ohmic contact to the buried 2DEG without destroying the magnetic properties of our crystal.

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A. Bove, F. Altomare, N. B. Kundtz, Albert M. Chang, Y. J. Cho, X. Liu, J. Furdyna. 2008-07-18. A novel technique to make Ohmic contact to a buried two-dimensional electron gas in a molecular-beam-epitaxy grown $GaAs/Al_{0.3}Ga_{0.7}As$ heterostructure with Mn $δ$-doping. https://arxiv.org/abs/0802.3863

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