Disappearence of the Aharonov-Bohm Effect for Interacting Electrons in a ZnO Quantum Ring

TL;DR

This study investigates how strong electron interactions and magnetic effects in ZnO quantum rings alter the Aharonov-Bohm effect, showing it can be suppressed or made aperiodic by changing electron number.

Contribution

It reveals that in ZnO quantum rings, the Aharonov-Bohm effect depends on electron number and can vanish with more electrons, unlike in conventional systems.

Findings

AB oscillations become aperiodic with two electrons

AB oscillations disappear with three electrons

Electron number controls the AB effect in ZnO rings

Abstract

The electronic states and optical transitions of a ZnO quantum ring containing few interacting electrons in an applied magnetic field are found to be very different from those in a conventional semiconductor system, such as a GaAs ring. The strong Zeeman and Coulomb interaction of the ZnO system, exert a profound influence on the electron states and on the optical properties of the ring. In particular, our results indicate that the Aharonov-Bohm (AB) effect in a ZnO quantum ring strongly depends on the electron number. In fact, for two electrons in the ZnO ring, the AB oscillations become aperiodic, while for three electrons (interacting) the AB oscillations completely disappear. Therefore, unlike in conventional quantum ring topology, here the AB effect (and the resulting persistent current) can be controlled by varying the electron number.