Nonreciprocal nanoparticle refrigerators: design principles and constraints

TL;DR

This paper demonstrates the design and analysis of nano refrigerators utilizing nonreciprocal forces, combining molecular dynamics simulations with stochastic thermodynamics to predict heat transfer, fluctuations, and efficiency.

Contribution

It introduces a minimal Langevin model with an effective friction parameter to analytically predict heat and work fluctuations in nonreciprocal nano refrigeration.

Findings

Nano refrigerators can transfer heat from cold to hot reservoirs using nonreciprocal forces.

Theoretical predictions match molecular dynamics simulations with a single unknown parameter.

Design principles for minimal entropy production and control of heat flow fluctuations are established.

Abstract

We study the heat transfer between two nanoparticles held at different temperatures that interact through nonreciprocal forces, by combining molecular dynamics simulations with stochastic thermodynamics. Our simulations reveal that it is possible to construct nano refrigerators that generate a net heat transfer from a cold to a hot reservoir at the expense of power exerted by the nonreciprocal forces. Applying concepts from stochastic thermodynamics to a minimal under-damped Langevin model, we derive exact analytical expressions predictions for the fluctuations of work, heat, and efficiency, which reproduce thermodynamic quantities extracted from the molecular dynamics simulations. The theory only involves a single unknown parameter, namely an effective friction coefficient, which we estimate fitting the results of the molecular dynamics simulation to our theoretical predictions. Using this framework, we also establish design principles which identify the minimal amount of entropy production that is needed to achieve a certain amount of uncertainty in the power fluctuations of our nano refrigerator. Taken together, our results shed light on how the direction and fluctuations of heat flows in natural and artificial nano machines can be accurately quantified and controlled by using nonreciprocal forces.