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arXiv · cond-mat/9612115

Screening of persistent currents in mesoscopic metal rings

Axel Voelker·Peter Kopietz
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Abstract

The effect of the Coulomb-interaction on persistent currents in disordered mesoscopic metal rings threaded by a magnetic flux $ϕ$ is studied numerically. We use the simplest form of ``self-consistent'' Hartree theory, where the spatial variations of the self-consistent Hartree potential are ignored. In this approximation the self-consistent Hartree energies are simply obtained by diagonalizing the non-interacting system via the Lanczos method and then calculating the (disorder-dependent) particle number on the ring self-consistently. In the diffusive regime we find that the variance of the total particle number is strongly reduced, in agreement with the prediction of the random-phase approximation. On the other hand, the variance of the number of energy levels in a small interval below the Fermi energy is not affected by the Coulomb interaction.

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Axel Voelker, Peter Kopietz. 1996-12-12. Screening of persistent currents in mesoscopic metal rings. https://doi.org/10.1007/s002570050324

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