Non-Lagrangian approach for coupled complex Ginzburg-Landau systems with higher order-dispersion

TL;DR

This paper introduces a semi-analytical collective variable approach to analyze coupled complex Ginzburg-Landau systems with higher order dispersion in fiber lasers, focusing on pulse symmetry, minimum fiber length, and effects of dispersion and coupling.

Contribution

It presents a novel semi-analytical method incorporating third-order dispersion to study pulse evolution and symmetry in coupled Ginzburg-Landau systems, including effects of intercore coupling.

Findings

Strong intercore coupling reduces fiber length needed for pulse symmetry.

Third-order dispersion increases pulse width and energy, and induces chaotic behavior.

Asymmetric initial pulses influence the evolution and bifurcation patterns.

Abstract

It is known that after a particular distance of evolution in fiber lasers, two (input) asymmetric soliton like pulses emerge as two (output) symmetric pulses having same and constant energy. We report such a compensation technique in dispersion managed fiber lasers by means of a semi-analytical method known as collective variable approach (CVA) with including third-order dispersion (TOD). The minimum length of fiber laser, at which the output symmetric pulses are obtained from the input asymmetric ones, is calculated for each and every pulse parameters numerically by employing Runge-Kutta fourth order method. The impacts of intercore linear coupling, asymmetric nature of initial parameters and TOD on the evolution of pulse parameters and on the minimum length are also investigated. It is found that strong intercore linear coupling and asymmetric nature of input pulse parameters result in the reduction of fiber laser length. Also, the role of TOD tends to increase the width of the pulses as well as their energies. Besides, chaotic patterns and bifurcation points on the minimum length of the fiber owing to the impact of TOD are also reported in a nutshell.