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Positive Magnetoresistance of Composite Fermions in Laterally Modulated Structures

S. D. M. Zwerschke·R. R. Gerhardts
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Abstract

Adopting the mean-field composite fermion picture, we describe the magneto-transport properties of a two-dimensional electron gas with laterally modulated density around filling factor 1/2. The occurrence of a strong positive magnetoresistance at low effective magnetic fields as well as Weiss oscillations, which were observed in recent experiments in such systems, can be explained within a semi-classical Boltzmann equation approach, provided one goes beyond a second order approximation in the modulation strength.

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S. D. M. Zwerschke, R. R. Gerhardts. 1999-06-18. Positive Magnetoresistance of Composite Fermions in Laterally Modulated Structures. https://arxiv.org/abs/cond-mat/9906296

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