Phases dynamics in VCSELs with delayed optical feedback and cross re-injection

TL;DR

This paper theoretically analyzes the complex polarization dynamics of VCSELs with delayed optical feedback and cross re-injection, revealing phase-based behaviors and modal structures, including known Lang-Kobayashi modes.

Contribution

It introduces a reduced phase-based dynamical system for VCSEL polarization dynamics with double feedback, unifying various modal behaviors and reinterpreting switching dynamics.

Findings

Dynamics confined near the equatorial plane of the Stokes sphere.

Recovery of Lang-Kobayashi and Giudici et al. modes.

Square wave switching reinterpreted as phase kinks.

Abstract

We study theoretically the non linear polarization dynamics of Vertical-Cavity Surface-Emitting Lasers in the presence of an external cavity providing delayed optical feedback and cross polarization re-injection. We show that far from the laser threshold, the dynamics remains confined close to the equatorial plane of a Stokes sphere of a given radius and we reduce the dynamics to a dynamical system composed of two phases: the orientation phase of the quasi-linear polarization and the optical phase of the field. We explore the complex modal structure given by the double feedback configuration and recovers as particular cases the Lang-Kobayashi modes and the modes founds by Giudici et al. [1]. We also re-interpret the square waves switching dynamics as phase kinks.