Persistent Currents in Interacting Aharonov-Bohm Interferometers and Their Enhancement by Acoustic Radiation

We consider an Aharonov-Bohm interferometer, connected to two electronic reservoirs, with a quantum dot embedded on one of its arms. We find a general expression for the persistent current at steady state, valid for the case where the electronic system is free of interactions except on the dot. The result is used to derive the modification in the persistent current brought about by coupling the quantum dot to a phonon source. The magnitude of the persistent current is found to be enhanced in an appropriate range of the intensity of the acoustic source.

Figure 1

An ABI, containing a quantum dot on its upper arm and threaded by a magnetic flux $\Phi$. The wavy line symbolizes the phonons radiated by the phonon source into the dot. The lower arm of the ABI contains a “reference” site. The ABI is connected to two electronic reservoirs whose chemical potentials are either equal or have a small difference, allowing a current $I$ to flow from the left to the right.