Quantum fluid effects and parametric instabilities in microcavities

TL;DR

This paper explores the non-equilibrium behavior of microcavity polariton fluids, revealing how collective excitations influence phenomena like superfluidity and Cherenkov effects through parametric instabilities and Rayleigh scattering.

Contribution

It provides a detailed theoretical analysis of polariton fluid dynamics, highlighting novel collective excitation spectra and their observable effects in non-equilibrium microcavity systems.

Findings

Observation of Bogolubov-like polariton excitations

Identification of polariton superfluidity and Cherenkov effects

Predicted far-field and near-field scattering images

Abstract

We present a description of the non-equilibrium properties of a microcavity polariton fluid, injected by a nearly-resonant continuous wave pump laser. In the first part, we point out the interplay between the peculiar dispersion of the Bogolubov-like polariton excitations and the onset of polariton parametric instabilities. We show how collective excitation spectra having no counterpart in equilibrium systems can be observed by tuning the excitation angle and frequency. In the second part, we explain the impact of these collective excitations on the in-plane propagation of the polariton fluid. We show that the resonant Rayleigh scattering induced by artificial or natural defects is a very sensitive tool to show fascinating effects such as polariton superfluidity or polariton Cherenkov effect. We present a comprehensive set of predicted far-field and near-field images for the resonant Rayleigh scattering emission.