Observation of dressed intra-cavity dark states

TL;DR

This paper reports the experimental observation of dressed intra-cavity dark states in a cold atom-cavity system, revealing a splitting of the cavity EIT peak into two, which aligns with theoretical predictions.

Contribution

First experimental demonstration of dressed intra-cavity dark states in a cold atom-cavity system, confirming semiclassical theoretical models.

Findings

Observation of split transmission peaks indicating dressed intra-cavity dark states

Frequency separation of peaks matches the Rabi frequency of the pump laser

Experimental results agree with theoretical semiclassical analysis

Abstract

Cavity electromagnetically induced transparency in a coherently prepared cavity-atom system is manifested as a narrow transmission peak of a weak probe laser coupled into the cavity mode. We show that with a resonant pump laser coupling the cavity-confined four-level atoms from free space, the narrow transmission peak of the cavity EIT is split into two peaks. The two peaks represent the dressed intra-cavity dark states and have a frequency separation approximately equal to the Rabi frequency of the free-space pump laser. We observed experimentally the dressed intra-cavity dark states in cold Rb atoms confined in a cavity and the experimental results agree with theoretical calculations based on a semiclassical analysis.