Complex nonlinear dynamics of polarization and transverse modes in a broad-area VCSEL

TL;DR

This paper explores the complex nonlinear and chaotic polarization and transverse mode dynamics in broad-area VCSELs, revealing bifurcations linked to mode competition and polarization changes, highlighting their intricate behavior compared to single-mode VCSELs.

Contribution

It provides a comprehensive analysis of polarization, spectral, near-field, and temporal dynamics in broad-area VCSELs, emphasizing the role of spatial and polarization degrees of freedom in mode competition.

Findings

Bifurcations coincide with changes in transverse modes and polarization.

Fluctuations at birefringence splitting frequencies develop through bifurcations.

Dynamics are more complex than in single-mode VCSELs.

Abstract

Lasers can exhibit nonlinear and chaotic dynamics driven by the interaction of multiple lasing modes, and investigating the different scenarios of mode competition and bifurcations of their dynamics is of great interest on a fundamental level as well as in view of applications. We study the dynamics of a broad-area vertical-cavity surface-emitting laser (VCSEL) in solitary continuous-wave operation with a comprehensive investigation of its polarization state, lasing spectra, near-field distributions, and temporal dynamics. Fluctuations at the frequency of birefringence splitting and other frequency components develop in a series of bifurcations. The bifurcations coincide with changes of the transverse lasing modes and/or the polarization state, demonstrating the importance of both the spatial and polarization degrees of freedom for mode competition. As a consequence, the inherent nonlinear dynamics of broad-area VCSELs is significantly more complex than the dynamics of VCSELs with a single spatial mode.