Formation dynamics of exciton polariton vortices created by non-resonant annular pumping

TL;DR

This paper investigates how exciton polariton vortices form spontaneously in an optical annular trap created by ring-shaped laser pulses, analyzing their orbital angular momentum and formation dynamics with high temporal resolution.

Contribution

It introduces a novel all-optical method to study the real-time formation and dynamics of exciton polariton vortices with orbital angular momentum detection.

Findings

Vortices form spontaneously in the annular trap.

Orbital angular momentum modes are identified during formation.

Ring diameter and power influence vortex formation dynamics.

Abstract

We study the spontaneous formation of exciton polariton vortices in an all-optical non-resonantly excited annular trap, which is formed by ring-shaped subpicosecond laser pulses. Since the light emitted by these vortices carries orbital angular momentum (OAM) corresponding to their topological charge, we apply a dedicated OAM spectroscopy technique to detect the OAM of the measurement signal with picosecond time resolution. This allows us to identify the formation of OAM modes and investigate the dynamics of the vortex formation process. We also study the power dependence of this process and how the ring diameter influences the formation of OAM modes.