Cavity-Enhanced Rydberg Atomic Superheterodyne Receiver

TL;DR

This paper demonstrates a cavity-enhanced Rydberg atomic superheterodyne receiver that significantly improves microwave electric field measurement sensitivity by amplifying atom-light interactions using an optical cavity, achieving about 19 dB enhancement.

Contribution

The work introduces a cavity-enhanced approach that substantially boosts the sensitivity of Rydberg-based microwave detection systems, surpassing traditional free-space methods.

Findings

Sensitivity improved by approximately 19 dB.

Optical cavity amplifies atom-light interaction.

Enhanced detection performance for microwave fields.

Abstract

High-sensitivity measurements of the microwave electric field are important in applications of communication and metrology. \replaced{The sensitivity of traditional Rydberg superheterodyne receivers in free space is effectively determined by the signal-to-noise ratio (SNR), which is often considered equivalent to sensitivity in practical sensing applications.}{The sensitivity of the traditional Rydberg superheterodyne receivers in free space is limited by signal-to-noise contrast.} In this work, we demonstrate a cavity-enhanced receiver, where an optical cavity significantly amplifies the interaction between the probe light and cesium atoms, which substantially improves the signal-to-noise ratio via enhancing the expansion coefficient \( \kappa \). \added{Here, $\kappa$ is the edge slope of the single peak obtained by fitting the double-peak EIT-AT spectrum, characterizing the response of the probe light to the frequency detuning of the coupling laser.}The sensitivity is thus boosted by a factor of approximately 19 dB. This study highlights the pivotal role of optical cavities in advancing Rydberg-based detection systems, offering a promising approach for high-sensitivity microwave electric field measurements.