Parametric Hypersensitivity and Transport in the Steady-State Open-System Holstein Model

TL;DR

This paper investigates the extreme sensitivity of the nonequilibrium steady state in an open-system Holstein model to system parameters, linking spectral features to transport optimization.

Contribution

It introduces a kinetic model to analyze hypersensitivity in the Holstein model and connects spectral avoided crossings to transport properties in open quantum systems.

Findings

Hypersensitivity occurs only in intermediate environmental regimes.

Transport can be optimized by tuning both closed- and open-system parameters.

Spectral avoided crossings are linked to steady-state hypersensitivity.

Abstract

We demonstrate that the nonequilibrium steady state (NESS) of an open-system Holstein model with linear bias displays extreme sensitivity to the closed system parameters. This sensitivity is shown to correspond to avoided crossings in the closed system spectrum, as previously demonstrated in the Rabi model. We then develop a kinetic model to analyze the effects of environmental parameters on NESS hypersensitivity. This reveals that hypersensitivity only exists in intermediate environmental parameter regimes, a prediction that is verified numerically. The inherent spatial character of the Holstein model offers a natural connection to transport, revealing that transport properties in the steady-state regime can be optimized by simultaneously coordinating the closed- and open-system parameters.