Coherent control of artificial molecules using an Aharonov-Bohm magnetic flux

TL;DR

This paper demonstrates that by varying the magnetic flux in an Aharonov-Bohm interferometer, one can control the quantum states of artificial molecules without direct coupling, revealing a flux-dependent crossover from symmetric to anti-symmetric states.

Contribution

It introduces a method to achieve continuous control of molecular states in double quantum dots via magnetic flux, without requiring direct coupling.

Findings

The molecular state crossover depends on the AB flux.

The quantum state exhibits a $4 extpi$ period, unlike the transport current.

Flux tuning enables control of artificial molecule states.

Abstract

Bonding and anti-bonding states of artificial molecules have been realized in experiments by directly coupling two quantum dots. Without a direct coupling between two nearby quantum dots, here we show that a continuous crossover, from symmetric to anti-symmetric molecular state, can be achieved by changing the flux through a double quantum dot Aharonov-Bohm (AB) interferometer. We explicitly present the flux-dependent real-time processes of molecular-state formation. In contrast to the transport current, which has a $2\pi$ period, the quantum state of the DQD molecule has a $4\pi$ period in the AB flux.