Abstract:
Ultra short optical pulses hold numerable applications yet their growth dynamics are not very well studied. This thesis considers an article by Mark Popov and Omri Gat that presents the results from a simulation using the Hauss master equation on a modelocking laser producing ultrashort pulses after a significant number of iterations. They have set their laser to start out from the continuous wave solution, where in this thesis it is argued how noise would make a more realistic initial condition for the system. Changing the initial condition to start out from noise as opposed to the continous wave state, would see the pulse form around ten times faster. Simulating the same laser using different maps for each component sees a difference in the stability of the fixed point of the continous wave, however do confirm how noise would make the system modelock faster. On top of the initial conditions, other factors affecting the speed with which the system modelocks are investigated, with the strengths of the gain medium and of the saturable absorber having the greatest impact. Afterwards the thesis proceeds to investigate the growth dynamics to see if the continuous wave state at any point would appear in between turning the system on and the laser modelocking, only to find this is not the case, is the system assumed to start out from noise. Lastly the properties of the created pulse is investigated to find double pulses as well as two- and three cycle regimes appearing depending on the laser cavity.