Realization of a Rydberg-dressed Ramsey interferometer and electrometer

TL;DR

This paper demonstrates a Rydberg-dressed Ramsey interferometer using ultracold potassium atoms, enabling precise measurements of atom-light interactions, coherence decay, and electric fields, with potential for advanced quantum sensing.

Contribution

It introduces an experimental realization of a Rydberg-dressed Ramsey interferometer that combines high coherence with controllable Rydberg state coupling for enhanced metrological applications.

Findings

Achieved sub-kilohertz accuracy in measuring Rydberg atom-light coupling and decay rates.

Demonstrated high-sensitivity electric field measurements using the interferometer.

Showed compatibility of ground-state coherence with Rydberg state interactions.

Abstract

We present the experimental realization and characterization of a Ramsey interferometer based on optically trapped ultracold potassium atoms, where one state is continuously coupled by an off-resonant laser field to a highly-excited Rydberg state. We show that the observed interference signals can be used to precisely measure the Rydberg atom-light coupling strength as well as the population and coherence decay rates of the Rydberg-dressed states with sub-kilohertz accuracy and for Rydberg state fractions as small as one part in $10^{6}$. We also demonstrate an application for measuring small, static electric fields with high sensitivity. This provides the means to combine the outstanding coherence properties of Ramsey interferometers based on atomic ground states with a controllable coupling to strongly interacting states, thus expanding the number of systems suitable for metrological applications and many-body physics studies.