Stochastic thermodynamics and the Ericsson nano engine -- Efficiency from equilibrium results

TL;DR

This paper investigates the efficiency of a quantum Ericsson cycle with a charged oscillator in a magnetic field, using stochastic thermodynamics and quantum Langevin equations, revealing how system-bath coupling influences efficiency.

Contribution

It introduces a quantum thermodynamic analysis of the Ericsson cycle using Langevin equations, highlighting the impact of system-bath coupling on efficiency optimization.

Findings

Efficiency can be maximized by tuning system-bath coupling strength.

Efficiency depends on magnetic field values between which the cycle operates.

Numerical results are obtained in the quasi-static regime.

Abstract

In this work, we study an Ericsson cycle whose working substance is a charged (quantum) oscillator in a magnetic field that is coupled to a heat bath. The resulting quantum Langevin equations with built-in noise terms encapsulate a thermodynamic structure and allow for the computation of the efficiency of the cycle. We numerically compute the efficiency of the cycle in the quasi-static regime using the steady-state thermodynamic functions of the system. Interestingly, it is found that by increasing the system-bath coupling strength, the efficiency of the cycle can be tuned to a maximum. We also explore the behavior of the efficiency as a function of the pair of magnetic-field values between which the cycle is operated.