Persistent currents in mesoscopic cavities with surface roughness

TL;DR

This paper investigates how surface roughness in mesoscopic cavities influences persistent currents, revealing that localized border-states enhance the current in the ballistic regime at half filling.

Contribution

It demonstrates that surface roughness leads to border states that coherently increase persistent currents, a robustness not previously documented.

Findings

Border states contribute coherently to persistent current

Surface roughness enhances the typical current magnitude

The enhancement is robust against size variations

Abstract

We consider a bidimensional discrete annular cavity with surface roughness (SR) threaded by a magnetic flux. In the ballistic regime and at half filling, localized border-states show up. These border states contribute coherentely to the persistent current and the magnitude of the typical current $I_{typ}$ is enhaced with respect to their value in the absence of confinement. This result is robust with respect to changes in the relevant lengths of the sample.