Transport of quantum excitations via local and nonlocal fluctuations

TL;DR

This paper explores how nonlocal noise, like incoherent hopping, influences quantum transport efficiency, revealing complex effects such as local extrema and a transition from quantum to classical behavior.

Contribution

It introduces the impact of nonlocal incoherent hopping on quantum transport, highlighting the resulting efficiency extrema and the quantum-to-classical crossover.

Findings

Incoherent hopping creates additional local extrema in transport efficiency.

The study demonstrates a crossover from quantum to classical random walk behavior.

Nonlocal noise can enhance or modify transport efficiency in quantum systems.

Abstract

In quantum systems, one usually seeks to minimize dephasing noise and disorder. The efficiency of transport in a quantum system is usually degraded by the presence of noise and disorder. However, it has been shown that the combination of the two can lead to significantly more efficiency than each by itself. Here, we consider how the addition of nonlocal noise, in the form of incoherent hopping, affects the transport efficiency. We show that incoherent hopping introduces additional local extrema in the efficiency function and investigate the crossover from a quantum random walk to a classical random walk.