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A Hartree-Fock Study of Persistent Currents in Disordered Rings

A. Kambili·C. J. Lambert·J. H. Jefferson
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Abstract

For a system of spinless fermions in a disordered mesoscopic ring, interactions can give rise to an enhancement of the persistent current by orders of magnitude. The increase in the current is associated with a charge reorganization of the ground state. The interaction strength for which this reorganization takes place is sample-dependent and the log-averages over the ensemble are not representative. In this paper we demonstrate that the Hartree-Fock method closely reproduces results obtained by exact diagonalization. For spinless fermions subject to a short-range Coulomb repulsion U we show that due to charge reorganization the derivative of the persistent current is a discontinuous function of U. Having established that the Hartree-Fock method works well in one dimension, we present corresponding results for persistent currents in two coupled chains.

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A. Kambili, C. J. Lambert, J. H. Jefferson. 1999-01-29. A Hartree-Fock Study of Persistent Currents in Disordered Rings. https://doi.org/10.1103/physrevb.60.7684

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