On optimal currents of indistinguishable particles

TL;DR

This paper develops a rigorous framework to analyze steady-state currents of indistinguishable particles, providing bounds and identifying enhancement mechanisms in weak coupling regimes, applicable to fermionic and bosonic systems.

Contribution

It introduces a general mathematical framework for non-interacting and weakly interacting particles, deriving bounds and revealing symmetry effects in particle currents.

Findings

Derived tight bounds for fermionic and bosonic steady state currents.

Identified a symmetry-induced enhancement mechanism in weak coupling regimes.

Applicable to systems with small inter-particle interactions.

Abstract

We establish a mathematically rigorous, general and quantitative framework to describe currents of non- (or weakly) interacting, indistinguishable particles driven far from equilibrium. We derive tight upper and lower bounds for the achievable fermionic and bosonic steady state current, respectively, which can serve as benchmarks for special cases of interacting many-particle dynamics. For fermionic currents, we identify a symmetry-induced enhancement mechanism in parameter regimes where the coupling between system and reservoirs is weak. This mechanism is broadly applicable provided the inter-particle interaction strength is small as compared to typical exchange interactions.