Unidirectional vortex waveguides and multistable vortex pairs in polariton condensates

TL;DR

This paper explores the creation and control of vortex waveguides in polariton condensates, demonstrating unidirectional vortex propagation and multistable vortex pairs using specially designed pump intensity profiles.

Contribution

It introduces a novel method to generate unidirectional vortex waveguides and multistable vortex pairs in polariton condensates through tailored pump intensity grooves.

Findings

Dark-ring states with $$-phase jumps can be formed in the condensate.

Multiple vortex-pair states are stable within the same dark ring.

Vortex waveguides enable unidirectional vortex transport.

Abstract

Vortices carrying quantized topological charges have potential application in information processing. In this work, we investigate vortex carriers and waveguides in microcavity polariton condensates, nonresonantly excited by a homogeneous pump with intensity grooves. An intensity groove with a ring shape in the pump gives rise to dark-ring states of the condensate with a $\pi$-phase jump, akin to dark solitons. The dark-ring states can be destroyed by a stronger density of the surrounding condensate and reduce into vortex-antivortex pairs. Multiple vortex-pair states are found to be stable in the same dark ring of the pump. When the pump ring is broader, higher-order dark states with multiple $\pi$-phase jumps can be obtained and interestingly they can be used to construct vortex waveguides. If a single vortex is imprinted in such waveguides, it can travel in a particular direction, showing one-way transportation. In other words, an imprinted vortex with a certain charge in a specifically designed higher-order dark state is only allowed to propagate unidirectionally.