Tuning the Aharonov-Bohm effect with dephasing in nonequilibrium transport

TL;DR

This paper explores how dephasing influences the Aharonov-Bohm effect in a three-site quantum system, revealing that phase effects persist in waiting-time distributions despite suppression in steady-state current.

Contribution

It demonstrates the impact of dephasing on the AB effect in nonequilibrium transport and introduces the analysis of waiting-time distributions to observe phase effects.

Findings

Steady-state current shows non-monotonic dependence on gauge phase.

Phase dependence persists in waiting-time distributions at short times.

Phase rigidity is broken in waiting-time statistics due to interference.

Abstract

The Aharanov-Bohm (AB) effect, which predicts that a magnetic field strongly influences the wave function of an electrically charged particle, is investigated in a three site system in terms of the quantum control by an additional dephasing source. The AB effect leads to a non-monotonic dependence of the steady-state current on the gauge phase associated with the molecular ring. This dependence is sensitive to site energy, temperature, and dephasing, and can be explained using the concept of the dark state. Although the phase effect vanishes in the steady-state current for strong dephasing, the phase dependence remains visible in an associated waiting-time distribution, especially at short times. Interestingly, the phase rigidity (i.e., the symmetry of the AB phase) observed in the steady-state current is now broken in the waiting-time statistics, which can be explained by the interference between transfer pathways.