Self-starting soliton-modelocked femtosecond Cr(4+):YAG laser using an antiresonant Fabry-Pérot saturable absorber

Abstract

We set up a self-starting passively modelocked femtosecond Cr.4C/:YAG laser using a low-finesse an- tiresonant Fabry-P ´ erot saturable absorber (A-FPSA). Stable transform-limited pulses were produced without the criti- cal cavity alignment necessary for Kerr lens modelocking. We achieved 114-fs pulses with 94 mW output power at the telecommunication wavelength 1:5 mm. The pulse formation is demonstrated to be due to soliton modelocking. At higher intracavity energy multiple pulsing was observed and is ex- plained by the saturation behaviour of the A-FPSA. In the multipulsing regime a pulse width as short as 95 fs and an averaged output power of up to 395 mW have been obtained.