Coherent merging of counter-propagating exciton-polariton superfluids

TL;DR

This paper demonstrates how four resonantly pumped polariton fluids can synchronize and merge into a single superfluid state, revealing new insights into macroscopic coherence and topological excitation suppression in exciton-polariton systems.

Contribution

It introduces a novel experimental setup where multiple polariton fluids are coherently merged, showing the transition from independent fluids to a unified superfluid state.

Findings

Four polariton fluids synchronize at high density

Topological excitations vanish upon merging

Formation of a single superfluid from multiple sources

Abstract

We report the formation of a macroscopic coherent state emerging from colliding polariton fluids. Four lasers with random relative phases, arranged in a square, pump resonantly a planar microcavity, creating four coherent polariton fluids propagating toward each other. When the density (interactions) increases, the four fluids synchronise and the topological excitations (vortex or soliton) disappear to form a single superfluid.