Spectral correlations in disordered mesoscopic metals and their relevance for persistent currents

Axel Voelker; Peter Kopietz

doi:10.1142/s0217984996001577

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Spectral correlations in disordered mesoscopic metals and their relevance for persistent currents

Axel Voelker·Peter Kopietz

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Abstract

We use the Lanczos method to calculate the variance of the number of energy levels in an energy window of width E below the Fermi energy for non-interacting disordered electrons on a thin three-dimensional ring threaded by an Aharonov-Bohm flux . We find that for small E the flux-dependent part of the variance is well described by a well-known Feynman diagram involving two Cooperons. However, this result cannot be extrapolated to energies E where the energy-dependence of the average density of states becomes significant. We discuss consequences for persistent currents.

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Axel Voelker, Peter Kopietz. 1996-12-18. Spectral correlations in disordered mesoscopic metals and their relevance for persistent currents. https://doi.org/10.1142/s0217984996001577

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