Opening-Assisted Coherent Transport in the Deep Classical Regime

TL;DR

This paper investigates how quantum coherence can enhance transport efficiency in disordered open systems even under strong dephasing, identifying optimal conditions for maximum enhancement through analytic models and real biological systems.

Contribution

It provides analytic insights into quantum transport enhancement in the deep classical regime and applies these findings to biological systems like the FMO complex.

Findings

Quantum coherence can significantly enhance transport despite strong dephasing.

An optimal opening strength exists for maximum transport enhancement.

Results are supported by models and biological system analysis.

Abstract

We study quantum enhancement of transport in open systems in the presence of disorder and dephasing. Quantum coherence effects may significantly enhance transport in open systems even in the deep classical regime (where the decoherence rate is greater than the inter-site hopping amplitude), as long as the disorder is sufficiently strong. When the strengths of disorder and dephasing are fixed, there is an optimal opening strength at which the coherent transport enhancement is optimized. Analytic results are obtained in two simple paradigmatic tight-binding models of large systems: the linear chain and the fully connected network. The physical behavior is also reflected in the FMO photosynthetic complex, which may be viewed as intermediate between these paradigmatic models.