# Orientational alignment in Cavity Quantum Electrodynamics

## TL;DR

This paper investigates how strong light-matter interactions in cavity QED induce orientational alignment of dipoles, demonstrating that high density or low temperature leads to near-perfect alignment, with consistent results across multiple theoretical approaches.

## Contribution

It compares Monte Carlo, mean-field, and large deviation methods, showing their agreement in predicting dipole alignment in cavity QED systems.

## Key findings

- Alignment develops with a macroscopically occupied polariton mode
- Dipoles approach perfect alignment at high density or low temperature
- Different theoretical approaches yield consistent results

## Abstract

We consider the orientational alignment of dipoles due to strong matter light coupling, for a non-vanishing density of excitations. We compare various approaches to this problem in the limit of large numbers of emitters, and show that direct Monte Carlo integration, mean-field theory, and large deviation methods match exactly in this limit. All three results show that orientational alignment develops in the presence of a macroscopically occupied polariton mode, and that the dipoles asymptotically approach perfect alignment in the limit of high density or low temperature.