Pump power induced instability and hysteresis in an all-normal dispersion linear mode-locked fiber laser

Abstract

In this manuscript, experimental studies on the instability and hysteresis in an all-normal dispersion (ANDi) fiber laser have been presented. The laser was mode-locked by using a semiconductor saturable absorber mirror and a chirped fiber Bragg grating in linear cavity configuration and under the stable conditions it delivered stationary dissipative soliton pulses with characteristic rectangular-shaped steep-edged spectrum. With increasing the pump power, the laser transits to a non-stationary state with a near trapezoidal-shaped spectrum with significant temporal instabilities. The hysteresis associated with the state transition and variations in spectral characteristics has been studied including dispersive Fourier transform based analysis. Pump power induced state transition in an ANDi linear cavity with a physical saturable absorber without the influence of any physical polarization controller or apparent limitation due to spectral filtering is the key observation presented in this paper.