An ideal entropy transporter with finite power and vanishing fluctuation

TL;DR

This paper introduces a micro-magnet system that can transport entropy efficiently and reliably without thermodynamic forces, demonstrating the possibility of ideal entropy transport with finite power and minimal fluctuations.

Contribution

It presents a theoretical model showing entropy transport with finite power and vanishing fluctuations in a non-equilibrium steady state, challenging traditional limitations.

Findings

Entropy transport remains finite with vanishing fluctuations under strong magnetic fields.

The system operates without thermodynamic forces, relying solely on magnetic interactions.

No fundamental thermodynamic limitations prevent ideal entropy transport in this setup.

Abstract

We study a micro-magnet that interacts with a spin-polarized electric current, a heat bath, as well as a static magnetic field. The resulting non-equilibrium steady-state transports entropy between the current and the heat bath, without need of any thermodynamic force. In the limit of strong magnetic field, both the entropy production rate and the fluctuation of entropy transport become vanishingly small, whereas the average rate of entropy transport remains finite. Our results demonstrate that there is no fundamental limitation on the performance of thermodynamic engines other than the first and second laws of thermodynamics.