A large deviation theory perspective on nanoscale transport phenomena

TL;DR

This paper introduces a large deviation theory-based framework for analyzing fluctuations in nanoscale transport phenomena, linking microscopic current distributions to nonlinear transport responses in nonequilibrium systems.

Contribution

It develops a systematic approach to compute current distributions and relate their cumulants to nonlinear transport coefficients at the nanoscale.

Findings

Framework applies to ionic conductivities and heat conduction in nanostructures.

Provides a microscopic basis beyond traditional hydrodynamics.

Illustrated through several applications.

Abstract

Understanding transport processes in complex nanoscale systems, like ionic conductivities in nanofluidic devices or heat conduction in low dimensional solids, poses the problem of examining fluctuations of currents within nonequilibrium steady states and relating those fluctuations to nonlinear or anomalous responses. We have developed a systematic framework for computing distributions of time integrated currents in molecular models and relating cumulants of those distributions to nonlinear transport coefficients. The approach elaborated upon in this perspective follows from the theory of dynamical large deviations, benefits from substantial previous formal development, and has been illustrated in several applications. The framework provides a microscopic basis for going beyond traditional hydrodynamics in instances where local equilibrium assumptions break down, which are ubiquitous at the nanoscale.