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Direct observation of micron-scale ordered structure in a two-dimensional electron system

I. J. Maasilta·Subhasish Chakraborty·I. Kuljanishvili·S. H. Tessmer·M. R. Melloch
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Abstract

We have applied a novel scanned probe method to directly resolve the interior structure of a GaAs/AlGaAs two-dimensional electron system in a tunneling geometry. We find that the application of a perpendicular magnetic field can induce surprising density modulations that are not static as a function of the field. Near six and four filled Landau levels, stripe-like structures emerge with a characteristic wave length ~2 microns. Present theories do not account for ordered density modulations on this length scale.

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I. J. Maasilta, Subhasish Chakraborty, I. Kuljanishvili, S. H. Tessmer, M. R. Melloch. 2003-09-16. Direct observation of micron-scale ordered structure in a two-dimensional electron system. https://doi.org/10.1103/physrevb.68.205328

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