| Abstract: | We demonstrate a self-starting Kerr-lens mode-locked (KLM) Yb:YAG thin-disk oscillator operating in the regime of positive intracavity group-delay dispersion (GDD). It delivers 1.7?ps pulses at an average power of 17?W and a repetition rate of 40?MHz. Dispersive mirrors compress the pulses to a duration of 190?fs (assuming sech2 shape; Fourier limit: 150?fs) at an average power level of 11?W. To our knowledge, this is the first KLM thin-disk oscillator with positive GDD. Output powers of up to 30?W were achieved with an increased output coupler transmission and intracavity GDD. We demonstrate increase of the pulse energy with increasing positive intracavity GDD, limited by difficulties in initiating mode-locking. |
