An efficient non-linear Feshbach engine

TL;DR

This paper explores a Bose-Einstein condensate-based thermodynamic engine utilizing Feshbach resonances to control interactions, employing shortcuts to adiabaticity to improve efficiency and power output despite rapid operation.

Contribution

It introduces a novel Feshbach resonance-based engine with a shortcut to adiabaticity, enhancing performance in finite-time thermodynamic cycles.

Findings

Shortcut to adiabaticity reduces irreversible work.

Tunable nonlinearity improves engine efficiency.

Engine achieves high power output with minimized excitations.

Abstract

We investigate a thermodynamic cycle using a Bose-Einstein condensate with nonlinear interactions as the working medium. Exploiting Feshbach resonances to change the interaction strength of the BEC allows us to produce work by expanding and compressing the gas. To ensure a large power output from this engine these strokes must be performed on a short timescale, however such non-adiabatic strokes can create irreversible work which degrades the engine's efficiency. To combat this, we design a shortcut to adiabaticity which can achieve an adiabatic-like evolution within a finite time, therefore significantly reducing the out-of-equilibrium excitations in the BEC. We investigate the effect of the shortcut to adiabaticity on the efficiency and power output of the engine and show that the tunable nonlinearity strength, modulated by Feshbach resonances, serves as a useful tool to enhance the system's performance.