Journal of the Optical Society of America B

Influence of intra-cavity photons and Rydberg interactions on microwave electric field sensing in an atom–cavity coupled system

Aparajita Das, Md. Mabud Hossain, Jayanta K. Saha

Published Jan 21, 2025• 0 citations

Abstract

The effects of Rydberg interactions, such as van der Waals and dipole–dipole interactions, on the probe absorption, cavity transmission, and reflection in a microwave (MW)-mediated pump–probe laser-driven atom–cavity system are theoretically investigated. The results demonstrate that the nonlinear probe absorption is enhanced by increasing intra-cavity photon numbers and is significantly influenced by the external MW field. Notably, the presence of the MW field alters the characteristics of Autler–Townes (AT) peaks in the absorption spectra and modifies the transmission windows in the cavity-transmitted or reflected intensity profiles. These alterations may facilitate the optimization of Rydberg atom-based MW sensing in atomic environments. Furthermore, we show that the variations in cavity length can considerably affect the smallest detectable MW electric field. The resolution of transmitted and reflected signals is improved under the strong pump field condition. Finally, an MW electric field measurement technique based on the phases of cavity-transmitted and reflected light is proposed, considering the influence of Rydberg interactions.

DOI: 10.1364/josab.544554

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