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arXiv · 1306.3537

Anisotropic Fermi Contour of (001) GaAs Electrons in Parallel Magnetic Fields

D. Kamburov·M. A. Mueed·M. Shayegan·L. N. Pfeiffer·K. W. West·K. W. Baldwin·J. J. D. Lee·R. Winkler
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Abstract

We demonstrate a severe Fermi contour anisotropy induced by the application of a parallel magnetic field to high-mobility electrons confined to a 30-nm-wide (001) GaAs quantum well. We study commensurability oscillations, namely geometrical resonances of the electron orbits with a unidirectional, surface-strain-induced, periodic potential modulation, to directly probe the size of the Fermi contours along and perpendicular to the parallel field. Their areas are obtained from the Shubnikov-de Haas oscillations. Our experimental data agree semi-quantitatively with the results of parameter-free calculations of the Fermi contours but there are significant discrepancies.

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D. Kamburov, M. A. Mueed, M. Shayegan, L. N. Pfeiffer, K. W. West, K. W. Baldwin, J. J. D. Lee, R. Winkler. 2013-06-15. Anisotropic Fermi Contour of (001) GaAs Electrons in Parallel Magnetic Fields. https://doi.org/10.1103/physrevb.88.125435

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