Magnetotransport with two occupied subbands in a Si(100) inversion layer

S. G. Semenchinsky; L. Smrcka; J. Stehno

doi:10.1016/0375-9601(95)00809-7

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Magnetotransport with two occupied subbands in a Si(100) inversion layer

S. G. Semenchinsky·L. Smrcka·J. Stehno

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Abstract

We have studied an electron transport in inversion layers of high-mobility Si(100) samples. At high electron concentrations and temperatures below 4.2 K, two series of Shubnikov-de Haas oscillations have been observed. The temperature damping of the second series oscillations indicates that the second occupied subband belongs to the first energy level of the fourfold-degenerate ladder $0'$. Samples with two occupied subbans exhibit a strong anomalous negative magnetoresitance, reaching $\rm \approx 25 \%$ of a zero field value at $B =$ 12 T. The resistance decrease is more pronounced for lower temperatures and higher electron concentrations. We explain this behaviour by an increase of the second subband mobility due to the freezing-out of the scattering of $0'$ electrons. Based on the measured periods of SdH oscillations, we conclude that the electrons are distributed inhomogeneously beneath the sample gate.

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S. G. Semenchinsky, L. Smrcka, J. Stehno. 1995-07-31. Magnetotransport with two occupied subbands in a Si(100) inversion layer. https://doi.org/10.1016/0375-9601(95)00809-7

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