Quantum signatures in quadratic optomechanical heat engine with an atom in a tapered trap

TL;DR

This paper explores quantum effects in a single atom heat engine within a tapered trap, demonstrating that trap asymmetry is crucial for quantum enhancements in power output, beyond mere temperature reduction.

Contribution

It models a quadratic optomechanical system as a quantum heat engine and identifies conditions for quantum-enhanced performance, emphasizing trap asymmetry.

Findings

Quantum signatures depend on trap asymmetry.

Lowering temperature alone does not ensure quantum enhancement.

Asymmetric confinement leads to increased power output.

Abstract

We investigate how quantum signatures can emerge in a single atom heat engine consisting of an atom confined in a tapered trap and subject to hot and cold thermal reservoirs. A similar system was realized experimentally in Ref.[1]. We model such a system using a quadratic optomechanical model and identify an effective Otto cycle in the system's dynamics. We compare the engine's performance in the quantum and classical regimes by evaluating the power dissipated. We find that lowering the temperature is insufficient to make the single atom engine of Ref.[1] a genuine quantum-enhanced heat engine. We show that it is necessary to make the trap more asymmetric and confined to ensure that quantum correlations cause an enhancement in the power output.