Probing coherent quantum thermodynamics using a trapped ion

TL;DR

This paper experimentally demonstrates quantum corrections to classical thermodynamic relations using a trapped ion, confirming quantum effects' significance in thermodynamics at low temperatures.

Contribution

It provides the first experimental measurement of quantum corrections to the work fluctuation-dissipation relation in a controlled quantum system.

Findings

Quantum correction to the classical work FDR observed.

Results violate classical FDR by over 10.9 standard deviations.

Quantum correction vanishes at high temperatures, matching theory.

Abstract

Quantum thermodynamics is aimed at grasping thermodynamic laws as they apply to thermal machines operating in the deep quantum regime, a regime in which coherences and entanglement are expected to matter. Despite substantial progress, however, it has remained difficult to develop thermal machines in which such quantum effects are observed to be of pivotal importance. In this work, we report an experimental measurement of the genuine quantum correction to the classical work fluctuation-dissipation relation (FDR). We employ a single trapped ion qubit, realizing thermalization and coherent drive via laser pulses, to implement a quantum coherent work protocol. The results from a sequence of two-time work measurements display agreement with the recently proven quantum work FDR, violating the classical FDR by more than $10.9$ standard deviations. We furthermore determine that our results are incompatible with any SPAM error-induced correction to the FDR by more than 10 standard deviations. Finally, we show that the quantum correction vanishes in the high-temperature limit, again in agreement with theoretical predictions.