Characteristic molecular properties of one-electron double quantum rings under magnetic fields

TL;DR

This paper theoretically investigates the magnetic field-dependent molecular states of conduction electrons in coupled quantum rings, revealing Aharonov-Bohm oscillations and tunneling effects that influence energy levels and angular momentum.

Contribution

It introduces a novel setup with double quantum rings demonstrating Aharonov-Bohm effects even with zero net magnetic flux.

Findings

Periodic fluctuations of tunnel splitting near ground state crossings

Magnetic field dependence of ring angular momentum

Observation of Aharonov-Bohm oscillations without net flux

Abstract

The molecular states of conduction electrons in laterally coupled quantum rings are investigated theoretically. The states are shown to have a distinct magnetic field dependence, which gives rise to periodic fluctuations of the tunnel splitting and ring angular momentum in the vicinity of the ground state crossings. The origin of these effects can be traced back to the Aharonov-Bohm oscillations of the energy levels, along with the quantum mechanical tunneling between the rings. We propose a setup using double quantum rings which shows that Aharonov-Bohm effects can be observed even if the net magnetic flux trapped by the carriers is zero.