Reflectivity and transmissivity of an optical cavity coupled to two-level atoms: Coherence properties and the influence of atomic phase noise

TL;DR

This paper analytically investigates how atomic phase noise and dephasing affect the reflectivity, transmissivity, and coherence properties of an optical cavity coupled to two-level atoms, revealing the impact on the cavity's emission spectrum.

Contribution

It provides analytical expressions for reflection, transmission, and emission spectra considering atomic phase noise and dephasing effects.

Findings

Atomic dephasing reduces cavity coherence

Atomic phase noise broadens emission spectrum

Dephasing prevents cavity from maintaining a coherent state

Abstract

We consider N identical two-level atoms coupled to an optical cavity, which is coherently driven by an external field. In the limit of small atomic excitation, the reflection and transmission coefficients for both fields and intensities are calculated analytically. In addition, the frequency content of the cavity field and hence also the emission spectrum of the cavity is determined. It is discussed in particular how individual collisional dephasing and common atomic energy-level fluctuations prevent the cavity field from being in a coherent state, which in turn affects the outgoing fields.