Enhancement of Persistent Current on Multichannel Ring

TL;DR

This paper investigates how strong electron-electron interactions influence persistent currents in multichannel rings, revealing potential enhancement and the emergence of fractional Aharonov-Bohm effects.

Contribution

It demonstrates that interactions can enhance persistent current in multichannel rings and introduces the fractional p/q-Aharonov-Bohm effect in this context.

Findings

Persistent current proportional to the square of the number of channels

Maximum enhancement occurs at medium interaction strength U~V_F

Fractional p/q-Aharonov-Bohm effect appears with interactions

Abstract

We study the effect of strong electron-electron interactions on the persistent current in a multichannel ring with the aid of Bosonization and the Bethe ansatz equation discussed by Sutherland and Tsvelik. The interaction acts differently on a single and multichannel ring. If, in the first case, the current is suppressed, then in the second case the current may be enhanced. With the interaction the current is proportional to square of the number of channels. The maximum effect corresponds to medium values of the interaction, where $U\sim V_F$. The new phenomenon of the fractional p/q- Aharonov-Bohm effect appears for interacting electrons on the multichannel ring.