Nondiffracting Supertoroidal Pulses: Optical "K\'arm\'an vortex streets"

TL;DR

This paper introduces nondiffracting supertoroidal pulses with stable, vortex-like topological structures that resemble von Kármán vortex streets, offering potential for robust optical energy channels.

Contribution

The study presents the first demonstration of nondiffracting supertoroidal pulses with stable skyrmionic and vortex-ring fields that maintain their structure over long distances.

Findings

Nondiffracting supertoroidal pulses exhibit stable topological features.

Field structures resemble von Kármán vortex streets.

Potential applications in directed energy and telecommunications.

Abstract

Recently introduced supertoroidal light pulses [Nat. Commun. 15, 5891 (2021)] are a family of space-time nonseparable freespace electromagnetic excitations with unique topological properties including skyrmionic field configurations, fractal-like patterns of singularities, and extended areas of energy backflow. Here we report nondiffracting supertoroidal pulses (ND-STPs), propagation-robust skyrmionic and vortex-ring field that endure the singular configurations over arbitrary propagation distances. Intriguingly, the field structure in of ND-STPs has a strong similarity with a von K\'arm\'an vortex street, a pattern of swirling vortices observed in fluid and gas dynamics that is responsible for the "singing" of suspended telephone lines in wind. We argue that ND-STPs are of interest as directed energy channels for telecom applications.