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arXiv · 1111.4310

Linear non-hysteretic gating of a very high density 2DEG in an undoped metal-semiconductor-metal sandwich structure

K. Das Gupta·A. F. Croxall·W. Y. Mak·H. E. Beere·C. A. Nicoll·I. Farrer·F. Sfigakis·D. A. Ritchie
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Abstract

Modulation doped GaAs-AlGaAs quantum well based structures are usually used to achieve very high mobility 2-dimensional electron (or hole) gases. Usually high mobilities ($>10^{7}{\rm{cm}^{2}\rm{V}^{-1}\rm{s}^{-1}}$) are achieved at high densities. A loss of linear gateability is often associated with the highest mobilites, on account of a some residual hopping or parallel conduction in the doped regions. We have developed a method of using fully undoped GaAs-AlGaAs quantum wells, where densities $\approx{6\times10^{11}\rm{cm}^{-2}}$ can be achieved while maintaining fully linear and non-hysteretic gateability. We use these devices to understand the possible mobility limiting mechanisms at very high densities.

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K. Das Gupta, A. F. Croxall, W. Y. Mak, H. E. Beere, C. A. Nicoll, I. Farrer, F. Sfigakis, D. A. Ritchie. 2011-11-18. Linear non-hysteretic gating of a very high density 2DEG in an undoped metal-semiconductor-metal sandwich structure. https://doi.org/10.1088/0268-1242%2F27%2F11%2F115006

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