Abstract
We demonstrate a new scheme for the generation of high average power femtosecond pulses by incorporating an intracavity amplifier and a strained saturable Bragg reflector with low saturation fluence for self-starting mode locking. When the Ti:sapphire oscillator and intracavity amplifier are pumped at 10 W and 15 W, respectively, the average output power is as high as 1.62 W. The pulse duration is about 145 fs, and the peak power reaches 160 kW at a 68 MHz repetition rate. The pulse-formation time of 400 μs is sufficiently short to sustain stable mode locking.