Low-loss quantum-dot-based saturable absorber for efficient femtosecond pulse generation

We report the efficient generation of femtosecond pulses from a diode-pumped solid-state laser that has been passively mode locked using a quantum-dot-based saturable absorber. Average output powers up to 1.15W and transform-limited pulses as short as 114fs were obtained around 1040nm with a pulse repetition frequency of 107MHz from a diode-pumped Yb3+:KY(WO4)2 laser. The InGaAs quantum-dot saturable absorber was characterized to have a saturation fluence of 25μJ/cm2 and nonsaturable losses of less than 0.2% with an initial low-signal absorption of 2.5% at 1040nm.