Enhancement of Persistent Currents by Hubbard Interactions In Disordered 1D Rings: Avoided Level Crossings Interpretation

Abstract

We study effects of local electron interactions on the persistent current of one dimensional disordered rings. For different realizations of disorder we compute the current as a function of Aharonov-Bohm flux to zeroth and first orders in the Hubbard interaction. We find that the persistent current is {\em enhanced} by onsite interactions. Using an avoided level crossings approach, we derive analytic formulas which explain the numerical results at weak disorder. The same approach also explains the opposite effect (suppression) found for spinless fermion models with intersite interactions.

uuencoded: 17 pages, text in revtex, 7 figs in postscript

Cited by in corpus (6)

• Random Matrix Theories in Quantum Physics: Common Concepts
• Persistent currents of noninteracting electrons
• Spin and interaction effects on charge distribution and currents in one-dimensional conductors and rings within the Hartree-Fock approximation
• Magnetization of Mesoscopic Disordered Networks
• Recovery of the persistent current induced by the electron-electron interaction in mesoscopic metallic rings
• Ground State Spin Structure of Strongly Interacting Disordered 1D Hubbard Model