Time-delayed coupled chaotic semiconductor lasers show new types of synchronization: Experiment and theory

TL;DR

This paper explores new synchronization phenomena in coupled chaotic semiconductor lasers with time delays, demonstrating experimental and theoretical results that could enhance multi-user communication systems.

Contribution

It introduces novel types of synchronization in time-delay-coupled lasers, including shifted zero-lag and sub-lattice synchronization, expanding understanding of laser network dynamics.

Findings

Shifted zero-lag synchronization observed over long distances.

Shifted sub-lattice synchronization in quadrilateral geometries.

Generalized zero-lag synchronization without exact delay matching.

Abstract

Topologies of two, three and four time-delay-coupled chaotic semiconductor lasers are experimentally and theoretically found to show new types of synchronization. Shifted zero-lag synchronization is observed for two lasers separated by long distances even when their self-feedback delays are not equal. Shifted sub-lattice synchronization is observed for quadrilateral geometries while the equilateral triangle is zero-lag synchronized. Generalized zero-lag synchronization, without the limitation of precisely matched delays, opens possibilities for advanced multi-user communication protocols.