Berry phase and persistent current in disordered mesoscopic rings

TL;DR

This paper investigates how Berry phase influences persistent currents in disordered mesoscopic rings, revealing oscillations related to geometric flux and effects of magnetic dephasing, using diagrammatic perturbation theory.

Contribution

It introduces a novel quantum interference effect in disordered rings and calculates the disorder-averaged persistent current considering Berry phase effects.

Findings

Average current oscillates with geometric flux in the adiabatic regime.

The oscillation period is half that of a single ring.

Magnetic dephasing suppresses the persistent current.

Abstract

A novel quantum interference effect in disordered quasi-one-dimensional rings in the inhomogeneous magnetic field is reported. We calculate the canonical disorder averaged persistent current using the diagrammatic perturbation theory. It is shown that within the adiabatic regime the average current oscillates as a function of the geometric flux which is related to the Berry phase and the period becomes half the value of the case of a single one-dimensional ring. We also discuss the magnetic dephasing effect on the averaged current.