Transitions of various operation states in a dissipative soliton mode-locked fiber laser

摘要

Multiple-pulse generation is often achieved in a passively mode-locked fiber laser when the mode-locking mechanisms are overdriven. Under certain circumstances, passively harmonic mode-locking (HML) and bound state of multiple pulses can also be observed. In this paper, a three-state switchable dissipative soliton (DS) mode-locked fiber laser based on a semiconductor saturable absorber mirror (SESAM) has been experimentally demonstrated for the first time. With a pump power of-175 mW, operation states of multiple pulses (two pulses), 2nd-order HML and bound state of two DSs were observed by only adjusting the polarization controller (PC) inside the cavity. At a higher pump power level (-276 mW), operation states of multiple pulses (three pulses), 3rd-order HML and bound state of three DSs were observed by changing the state of the PC. From the experimental results, it seems that there is a correlative relationship among the three operation states (N pulses/Nth-order HML/ bound state of N pulses) for the DS fiber laser and these states are switchable by only adjusting the cavity birefringence with a PC under the same pump power level.