Ginzburg-Landau turbulence in quasi-CW Raman fiber lasers

TL;DR

This paper models quasi-continuous wave Raman fiber lasers using complex Ginzburg-Landau equations, revealing turbulent intensity fluctuations and polarization rogue waves, thus unifying understanding of different laser types.

Contribution

It introduces the first vector model for Raman fiber lasers based on Ginzburg-Landau equations, explaining turbulent dynamics and rogue waves observed experimentally.

Findings

Model accurately reproduces turbulent intensity fluctuations.

Identifies polarization rogue waves in Raman fiber lasers.

Suggests common physics between quasi-CW and mode-locked lasers.

Abstract

Fiber lasers operating via Raman gain or based on rare-earth doped active fibers are widely used as sources of CW radiation. However these lasers are only quasi-CW: their intensity fluctuates strongly on short time-scales. Here the framework of the complex Ginzburg-Landau equations, that are well known as an efficient model of mode-locked fiber lasers, is applied for the description of quasi-CW fiber lasers as well. The first ever vector model of a Raman fiber laser describes the experimentally observed turbulent-like intensity dynamics, as well as polarization rogue waves. Our results open debates about the common underlying physics of operation of very different laser types - quasi-CW lasers and passively mode-locked lasers.