Far-field resonance fluorescence from a dipole-interacting laser-driven cold atomic gas

TL;DR

This paper investigates the collective resonance fluorescence from dense, cold atomic gases with dipolar interactions, analyzing how many-body effects influence emitted light properties beyond weak driving conditions.

Contribution

It provides an exact analysis of the fluorescence dynamics in small geometries, revealing signatures of collective behavior and the impact of disorder in strongly interacting atomic gases.

Findings

Enhanced photon emission rates due to collective effects

Distinct features in the power spectrum indicating many-body interactions

Altered second-order correlation functions reflecting quantum correlations

Abstract

We analyze the temporal response of the fluorescence light that is emitted from a dense gas of cold atoms driven by a laser. When the average interatomic distance is smaller than the wavelength of the photons scattered by the atoms, the system exhibits strong dipolar interactions and collective dissipation. We solve the exact dynamics of small systems with different geometries and show how these collective features are manifest in the scattered light properties such as the photon emission rate, the power spectrum and the second-order correlation function. By calculating these quantities beyond the weak driving limit, we make progress in understanding the signatures of collective behavior in these many-body systems. Furthermore, we clarify the role of disorder on the resonance fluorescence, of direct relevance for recent experimental efforts that aim at the exploration of many-body effects in dipole-dipole interacting gases of atoms.