Parametric scattering of microcavity polaritons into ghost branches

TL;DR

This paper investigates the nonlinear scattering processes of microcavity polaritons, revealing ghost branches and extending theoretical models to better understand the eigenmodes and photoluminescence in these systems.

Contribution

It introduces experimental observation of ghost branches from polariton scattering and extends existing theoretical models to include driven polariton eigenmodes.

Findings

Observation of ghost branches from scattering within and between polariton branches

Extension of theoretical models to include driven polariton eigenmodes

Analysis of non-linear mixing effects in microcavity polaritons

Abstract

Polaritons of defined momentum and energy are excited resonantly on the lower polariton branch of a planar semiconductor microcavity in the strong coupling regime, and the spectrally and momentum resolved emission is analyzed. We observe ghost branches from scattering within the lower polariton branch, as well as from scattering to the middle polariton branch, showing the non-linear mixing between different branches. Extending the theoretical treatment of spontaneous parametric luminescence developed in Ciuti et al., Phys. Rev. B 63, 041303 (2001), the eigenmodes of the driven polariton system and its photoluminescence are modeled.