Geometric frustration in polygons of polariton condensates creating vortices of varying topological charge

TL;DR

This paper demonstrates the formation of stable, high-charge vortices in polariton condensates arranged in polygons, revealing a new way to study complex vortex states in non-equilibrium superfluid systems.

Contribution

It introduces a novel method of creating stable giant vortices in polariton condensates through geometric frustration in polygonal arrangements.

Findings

Stable large topological charge vortices observed in polariton polygons

Geometric frustration leads to vortex formation and stability

Potential new platform for studying superfluid vortex dynamics

Abstract

Vorticity is a key ingredient to a broad variety of fluid phenomena, and its quantised version is considered to be the hallmark of superfluidity. Circulating flows that correspond to vortices of a large topological charge, termed giant vortices, are notoriously difficult to realise and even when externally imprinted, they are unstable, breaking into many vortices of a single charge. In spite of many theoretical proposals on the formation and stabilisation of giant vortices in ultra-cold atomic Bose-Einstein condensates and other superfluid systems, their experimental realisation remains elusive. Polariton condensates stand out from other superfluid systems due to their particularly strong interparticle interactions combined with their non-equilibrium nature, and as such provide an alternative testbed for the study of vortices. Here, we non-resonantly excite an odd number of polariton condensates at the vertices of a regular polygon and we observe the formation of a stable discrete vortex state with a large topological charge as a consequence of antibonding frustration between nearest neighbouring condensates.