Extracting quantum work statistics and fluctuation theorems by single qubit interferometry

TL;DR

This paper presents an experimental method using single qubit interferometry to verify quantum fluctuation theorems, enabling the characterization of non-equilibrium quantum processes across various complex systems.

Contribution

It introduces a practical scheme to extract work statistics via Ramsey interferometry, applicable to diverse quantum systems, advancing experimental verification of quantum fluctuation relations.

Findings

Scheme successfully extracts work distribution characteristic function

Applicable to single particles, many-body systems, and spin chains

Demonstrated with a trapped ion quench experiment

Abstract

We propose an experimental scheme to verify the quantum non-equilibrium fluctuation relations using current technology. Specifically, we show that the characteristic function of the work distribution for a non-equilibrium quench of a general quantum system can be extracted from Ramsey interferometry of a single probe qubit. Our scheme paves the way for the full characterisation of non-equilibrium processes in a variety of complex quantum systems ranging from single particles to many-body atomic systems and spin chains. We demonstrate our idea using a time-dependent quench of the motional state of a trapped ion, where the internal pseudo-spin provides a convenient probe qubit.