Sensitivity of Rydberg-atom receiver to frequency and amplitude modulation of microwaves

TL;DR

This paper develops an analytical model and experimental setup to evaluate the sensitivity of Rydberg-atom-based microwave receivers to amplitude and frequency modulation, revealing optimal parameters for robust detection.

Contribution

It introduces a new analytical model for Rydberg atomic receiver response to AM and FM signals and demonstrates a novel detection configuration using circular polarizations.

Findings

Optimal parameters for Rydberg MW sensors identified

Experimental validation of the analytical model conducted

Detection of circularly polarized MW fields achieved

Abstract

Electromagnetically induced transparency (EIT) in atomic systems involving Rydberg states is known to be a sensitive probe of incident microwave (MW) fields, in particular those resonant with Rydberg-to-Rydberg transitions. Here we propose an intelligible analytical model of Rydberg atomic receiver's response to amplitude- (AM) and frequency-modulated (FM) signals, and compare it with experimental results: we present a setup that allows sending signals with either AM or FM and evaluating their efficiency with demodulation. Additionally, the setup reveals a new detection configuration, using all circular polarizations for optical fields and allowing detection of circularly polarized MW field, propagating colinearly with optical beams. In our measurements we systematically present that several parameters exhibit local optimum characteristics and then estimate these optimal parameters and working ranges, addressing the need to devise a robust Rydberg MW sensor and its operational protocol.