Optics Express

Laser modulation transfer phenomenon in a four-level heterodyne Rydberg atom system

Yu Tang, Hanbin Zhou, Chuang Yang, Shuang Ren, Siyuan Wang, Chenxi Lu

Published Jun 10, 2025• 0 citations

Abstract

This paper investigates the transfer of probe or coupling light modulation interference to density matrix elements in a four-level heterodyne Rydberg system. By combining the density matrix dynamical equations with power spectral density (PSD) analysis, we derive analytical solutions to describe this phenomenon. Our results demonstrate that coherence in multi-level systems fundamentally enables this transfer mechanism, thereby increasing the system's noise floor and degrading microwave detection sensitivity. Building on these findings, we establish a sensitivity-noise-constraint relationship to suppress the influence of noise.

DOI: 10.1364/oe.567239

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