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Valley splitting of AlAs two-dimensional electrons in a perpendicular magnetic field

Y. P. Shkolnikov·E. P. De Poortere·E. Tutuc·M. Shayegan
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Abstract

By measuring the angles at which the Landau levels overlap in tilted magnetic fields (the coincidence method), we determine the splitting of the conduction-band valleys in high-mobility two-dimensional (2D) electrons confined to AlAs quantum wells. The data reveal that, while the valleys are nearly degenerate in the absence of magnetic field, they split as a function of perpendicular magnetic field. The splitting appears to depend primarily on the magnitude of the perpendicular component of the magnetic field, suggesting electron-electron interaction as its origin.

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Y. P. Shkolnikov, E. P. De Poortere, E. Tutuc, M. Shayegan. 2002-07-17. Valley splitting of AlAs two-dimensional electrons in a perpendicular magnetic field. https://doi.org/10.1103/physrevlett.89.226805

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