Tunable dual-wavelength passively mode-locked Yb-doped fiber laser using SESAM

In this linear-cavity passively mode-locked laser based on semiconductor saturable absorber mirror,an Ybdoped fiber is shared by two branch cavities as gain medium.These two cavities can respectively output single-wavelength pulse with the wavelength tuning range of 1 009.7-1 057.6 nm and 1 011.6-1 052.6 nm by adjusting volume Bragg grating.When two cavities output pulses together,the dual-wavelength pulses with the maximum and minimum wavelength separation of 34.8 and 2.4 nm,respectively,are achieved by net gain equalization method to suppress mode competition at room temperature.The maximum pulse energies of dual-wavelength pulses are 0.47 and 0.33 nJ separately;their repetition rates are 11.39 and 11.41 MHz.