Correlation in superradiance: A closed-form approach to cooperative effects

TL;DR

This paper introduces a new closed-form method to analyze superradiance and cooperative effects, accounting for complex atomic interactions and quantum fluctuations, revealing that correlation, not entanglement, drives superradiance.

Contribution

A novel closed-form approach to model superradiance, including complex atomic and field interactions, and clarifying the role of correlation versus entanglement.

Findings

Initial radiation burst and broadening due to dipole interactions observed

Population of subradiant states can be estimated during decay

Correlation, not entanglement, is responsible for superradiance

Abstract

We have developed a novel method to describe superradiance and related cooperative and collective effects in a closed form. Using the method we derive a two-atom master equation in which any complexity of atomic levels, semiclassical coupling fields and quantum fluctuations in the fields can be included, at least in principle. As an example, we consider the dynamics of an initially inverted two-level system and show how even such in a simple system phenomena such as the initial radiation burst or broadening due to dipole-dipole interactions occur, but it is also possible to estimate the population of the subradiant state during the radiative decay. Finally, we find that correlation only, not entanglement is responsible for superradiance.