Evolution of collective N atom states in single photon superradiance

TL;DR

This paper provides analytical solutions for the evolution of collective N-atom states in single photon superradiance, highlighting the effects of virtual processes on decay dynamics and state trapping.

Contribution

It introduces analytical models for collective atomic state evolution, emphasizing the role of virtual processes in superradiance and state trapping.

Findings

Virtual processes slightly affect the rapid decay of timed Dicke states.

Long-term dynamics shift from exponential to power-law decay due to virtual processes.

Virtual processes enable slow decay in trapped states, altering their stability.

Abstract

We present analytical solutions for the evolution of collective states of N atoms. On the one hand is a (timed) Dicke state prepared by absorption of a single photon and exhibiting superradiant decay. This is in strong contrast to evolution of a symmetric Dicke state which is trapped for large atomic clouds. We show that virtual processes yield a small effect on the evolution of the rapidly decaying timed Dicke state. However, they change the long time dynamics from exponential decay into a power-law behavior which can be observed experimentally. For trapped states virtual processes are much more important and provide new decay channels resulting in a slow decay of the otherwise trapped state.