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Two-subband quantum Hall effect in parabolic quantum wells

C. Ellenberger·B. Simovic·R. Leturcq·T. Ihn·S. E. Ulloa·K. Ensslin·D. C. Driscoll·A. C. Gossard
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Abstract

The low-temperature magnetoresistance of parabolic quantum wells displays pronounced minima between integer filling factors. Concomitantly the Hall effect exhibits overshoots and plateau-like features next to well-defined ordinary quantum Hall plateaus. These effects set in with the occupation of the second subband. We discuss our observations in the context of single-particle Landau fan charts of a two-subband system empirically extended by a density dependent subband separation and an enhanced spin-splitting g*.

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C. Ellenberger, B. Simovic, R. Leturcq, T. Ihn, S. E. Ulloa, K. Ensslin, D. C. Driscoll, A. C. Gossard. 2006-02-10. Two-subband quantum Hall effect in parabolic quantum wells. https://doi.org/10.1103/physrevb.74.195313

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