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arXiv · 1410.6019

Ultra-high mobility two-dimensional electron gas in a SiGe/Si/SiGe quantum well

M. Yu. Melnikov·A. A. Shashkin·V. T. Dolgopolov·S. -H. Huang·C. W. Liu·S. V. Kravchenko
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Abstract

We report the observation of an electron gas in a SiGe/Si/SiGe quantum well with maximum mobility up to 240 m^2/Vs, which is noticeably higher than previously reported results in silicon-based structures. Using SiO, rather than Al_2O_3, as an insulator, we obtain strongly reduced threshold voltages close to zero. In addition to the predominantly small-angle scattering well known in the high-mobility heterostructures, the observed linear temperature dependence of the conductivity reveals the presence of a short-range random potential.

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M. Yu. Melnikov, A. A. Shashkin, V. T. Dolgopolov, S. -H. Huang, C. W. Liu, S. V. Kravchenko. 2015-03-05. Ultra-high mobility two-dimensional electron gas in a SiGe/Si/SiGe quantum well. https://doi.org/10.1063/1.4914007

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