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A Laterally Modulated 2D Electron System in the Extreme Quantum Limit

Sorin Melinte·Mona Berciu·C. Zhou·E. Tutuc·S. J. Papadakis·C. Harrison·E. P. De Poortere·Mingshaw Wu·P. M. Chaikin·M. Shayegan·R. N. Bhatt·R. A. Register
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Abstract

We report on magnetotransport of a two-dimensional electron system (2DES), located 32 nm below the surface, with a surface superlattice gate structure of periodicity 39 nm imposing a periodic modulation of its potential. For low Landau level fillings $ν$, the diagonal resistivity displays a rich pattern of fluctuations, even though the disorder dominates over the periodic modulation. Theoretical arguments based on the combined effects of the long-wavelength, strong disorder and the short-wavelength, weak periodic modulation present in the 2DES qualitatively explain the data.

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Sorin Melinte, Mona Berciu, C. Zhou, E. Tutuc, S. J. Papadakis, C. Harrison, E. P. De Poortere, Mingshaw Wu, P. M. Chaikin, M. Shayegan, R. N. Bhatt, R. A. Register. 2003-11-18. A Laterally Modulated 2D Electron System in the Extreme Quantum Limit. https://doi.org/10.1103/physrevlett.92.036802

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