Effects of Dipole-Dipole Interaction on the Transmitted spectrum of Two-level Atoms trapped in an optical cavity

TL;DR

This paper theoretically studies how dipole-dipole interactions influence the transmission spectrum of two atoms in an optical cavity, revealing effects on peak asymmetry, spectrum deformation, and atom-cavity decoupling.

Contribution

It introduces a method to analyze the spectrum by transforming the two-atom system into an effective single-atom model considering DDI effects.

Findings

DDI enhances effects at positive detunings

DDI causes spectrum deformation at higher excitations

Large DDI can decouple atom and cavity

Abstract

The transmission spectrum of two dipole-dipole coupled atoms interacting with a single-mode optical cavity in strong coupling regime is investigated theoretically for the lower and higher excitation cases, respectively. The dressed states containing the dipole-dipole interaction (DDI) are obtained by transforming the two-atom system into an effective single-atom one. We found that the DDI can enhance the effects resulting from the positive atom-cavity detunings but weaken them for the negative detunings cases for lower excitation, which can promote the spectrum exhibiting two asymmetric peaks and shift the heights and the positions of them. For the higher excitation cases, DDI can augment the atomic saturation and lead to the deforming of the spectrum. Furthermore, the large DDI can make the atom and the cavity decouple, making a singlet of the normal-mode spectrum.