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arXiv · 0903.1862

Temperature-dependent transport in a sixfold degenerate two-dimensional electron system on a H-Si(111) surface

Robert N. McFarland·Tomasz M. Kott·Luyan Sun·K. Eng·B. E. Kane
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Abstract

Low-field magnetotransport measurements on a high mobility (mu=110,000 cm^2/Vs) two-dimensional (2D) electron system on a H-terminated Si(111) surface reveal a sixfold valley degeneracy with a valley splitting <= 0.1 K. The zero-field resistivity rho_{xx} displays strong temperature dependence for 0.07 < T < 25 K as predicted for a system with high degeneracy and large mass. We present a method for using the low-field Hall coefficient to probe intervalley momentum transfer (valley drag). The relaxation rate is consistent with Fermi liquid theory, but a small residual drag as T->0 remains unexplained.

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Robert N. McFarland, Tomasz M. Kott, Luyan Sun, K. Eng, B. E. Kane. 2009-10-26. Temperature-dependent transport in a sixfold degenerate two-dimensional electron system on a H-Si(111) surface. https://doi.org/10.1103/physrevb.80.161310

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