SUPPRESSION OF PERSISTENT CURRENTS IN ONE-DIMENSIONAL DISORDERED RINGS BY THE COULOMB INTERACTION

The effects of the Coulomb interaction on persistent currents in disordered one-dimensional rings are investigated numerically. First, the effectiveness of the Hartree-Fock approximation is established on small systems. Then the calculations are performed for systems with 40 electrons in 100 sites. It is found that the amplitude of the average persistent current in the diffusive regime is suppressed as the strength of the Coulomb interaction increases. The suppression of the current is stronger in larger rings than in smaller ones. The enhancement of the current by the electron-electron interaction was not observed in the diffusive regime.