We investigate the impact of spectral filtering in mode-locked fiber lasers with an extended geometrical model. Our iterative model, which includes gain, loss and the pulse shaping effects of chromatic dispersion and self-phase modulation, is used to model the laser cavity dynamics. Simulations show that broadband pulses experience large losses from spectral filtering in the cavity, leading to a number of potential laser instabilities and outcomes such as multi-pulsing, periodic and chaotic states, or a single pulse which transitions to a higher energy state. For narrow band spectral filtering, the laser dynamics is dominated by the gain-loss dynamics in the cavity which causes multi-pulsing. For broadband spectral filtering, the nonlinearity induced spectral reshaping of the single pulse can lead to a discontinuous pulse energy transition that circumvents multi-pulsing. The inclusion of third order dispersion shows that the multi-pulsing instability is induced even in the case of broadband spectral filtering.
|Number of pages||9|
|Journal||IEEE Journal of Selected Topics in Quantum Electronics|
|Early online date||10 Nov 2017|
|Publication status||Published - May 2018|
- Mode-locked fiber lasers
- spectral filtering
- nonlinear dynamics