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Coulomb gap in the quantum Hall insulator

Michael Backhaus·Bodo Huckestein
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Abstract

We calculate numerically the spectrum of disordered electrons in the lowest Landau level at filling factor 1/5 using the self-consistent Hartree-Fock approximation for systems containing up to 400 flux quanta. Special attention is paid to the correct treatment of the q=0 component of the Coulomb interaction. For sufficiently strong disorder, the system is an insulator at this filling factor. We observe numerically a Coulomb gap in the single-particle density of states (DOS). The DOS agrees quantitatively with the predictions for classical point charges.

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Michael Backhaus, Bodo Huckestein. 2000-04-07. Coulomb gap in the quantum Hall insulator. https://doi.org/10.1142/s0217979201005842

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