Polariton ring condensates and sunflower ripples in an expanding quantum liquid

TL;DR

This paper investigates the formation of ring-shaped polariton condensates and sunflower ripple patterns in an expanding quantum liquid within semiconductor microcavities, revealing novel interference phenomena and spatial structures.

Contribution

It demonstrates the spontaneous formation of ring condensates and sunflower ripples due to self interference and Rayleigh scattering in an expanding polariton quantum liquid.

Findings

Ring condensates form from incoherent polaritons

Sunflower ripple patterns arise from self interference

Rayleigh scattering influences the spatial structures

Abstract

Optically pumping high quality semiconductor microcavities allows for the spontaneous formation of polariton condensates, which can propagate over distances of many microns. Tightly focussed pump spots here are found to produce expanding incoherent bottleneck polaritons which coherently amplify the ballistic polaritons and lead to the formation of unusual ring condensates. This quantum liquid is found to form a remarkable sunflower-like spatial ripple pattern which arises from self interference with Rayleigh-scattered coherent polariton waves in the Cerenkov regime.