Nonlinear Dynamics of a Passively Mode-Locked Fiber Laser Containing a Long-Period Fiber Grating

We report on a numerical investigation of the nonlinear dynamics of a passively mode-locked fiber laser containing a long period fiber grating. The model is based on the normalized complex Ginzburg-Landau equation and the nonlinear coupled mode equations of the grating. The numerical results indicate the existence of passive mode-locking and autosoliton generation in the cavity of the laser. Both single and bound soliton pulse trains exhibit period doubling bifurcations and a route to chaos as the normalized saturated gain is increased. Furthermore, we show the presence of long period pulsation, soliton sidebands and possible coexisting attractors excited by multisoliton formation and soliton energy quantization.