Passively Mode-locked Diode-pumped Yb:CaF2 Oscillator

Abstract

Passively modelocked diode-pumped solid-state lasers based on semiconductor saturable absorber mirrors and Kerr lens mode-locking which have demonstrated good performance in terms of pulse duration, peak power, pulse repetition rates and maintainability. Yb3+:CaF2 has been recognized as a good candidate for a highly efficient high power femtosecond laser. In this thesis, a passively mode-locked diode-pumped Yb3+:CaF2 oscillator has been developed. In the case of the SESAM mode-locking cavity, energetic Q-switched modelocked laser pulses were generated. A Kerr-lens mode-locked oscillator was constructed for continuous-wave modelocking operations by incorporating an additional optical element with an enhanced nonlinear Kerr coefficient, which represents the first such investigation for an Yb3+:CaF2 oscillator to our best knowledge. A 2-pulse per round trip KLM operation was obtained with 970 mW output power at 10 W pump and 164 MHz repetition rate. The output spectrum had a FWHM of 3 nm and centered at 1053 nm.