Dissipative Josephson vortices in annular polariton fluids

TL;DR

This paper investigates the formation and behavior of Josephson vortices in coupled annular polariton condensates, revealing how their structure depends on coupling strength and affects angular momentum transfer.

Contribution

It introduces the concept of dissipative Josephson vortices in polariton fluids and analyzes their dependence on coupling, providing new insights into topological defect dynamics in these systems.

Findings

Josephson vortices are stable topological defects in coupled polariton rings.

Coupling strength controls the structure and dynamics of the vortices.

Synchronous rotation occurs above a critical coupling, with phase slip events facilitating phase locking.

Abstract

We consider two concentric rings formed by bosonic condensates of exciton-polaritons. A circular superfluid flow of polaritons in one of the rings can be manipulated by acting upon the second annular polariton condensate. The complex coupling between the rings with different topological charges triggers nucleation of stable Josephson vortices (JVs) which are revealed as topological defects of the angular dependence of the relative phase between rings. Being dependent on the coupling strength, the structure of the JV governs the difference of the mean angular momenta of the inner and the outer rings. At the vanishing coupling the condensates rotate independently demonstrating no correlations of their winding numbers. At the moderate coupling, the interaction between two condensates tends to equalize their mean angular momenta despite of the mismatch of the winding numbers demonstrating the phenomenology of a drag effect. Above the critical coupling strength the synchronous rotation is established via the phase slip events.