Interaction-Induced Enhancement and Oscillations of the Persistent Current

  title={Interaction-Induced Enhancement and Oscillations of the Persistent Current},
  author={Charles A. Stafford and D. F. Wang},
  journal={Physical Review B},
The persistent current I in integrable models of multichannel rings with both short- and long-ranged interactions is investigated. I is found to oscillate in sign and increase in magnitude with increasing interaction strength due to interaction- induced correlations in the currents contributed by different channels. For sufficiently strong interactions, the contributions of all channels are found to add constructively, leading to a giant enhancement of I. Numerical results confirm that this… 
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