On the response of composite fermions to weak electrostatic potentials

Behnam Farid

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arXiv · cond-mat/9912156

On the response of composite fermions to weak electrostatic potentials

Behnam Farid

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Abstract

We establish that the response to static perturbations of two-dimensional electron systems (2DESs), exposed to magnetic field B, in states with the Landau-level filling fractions νclose to one such as 1/2, is singularly different from that of 2DESs at small |B|. Thus in addition to demonstrating the sever inadequacy of the treatment of composite fermions as non-interacting particles, we show, in contradiction to a recent theoretical finding, that the physical origin of the observed behaviour of the dc longitudinal magneto-resistivity for νclose to 1/2 in periodically modulated 2DESs remains to be determined.

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Behnam Farid. 1999-12-09. On the response of composite fermions to weak electrostatic potentials. https://arxiv.org/abs/cond-mat/9912156

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