93 fs pulses at watt-level powers from a diode pumped Yb:CaGdAlO4 laser

Abstract We investigated the performance of diode pumped mode-locked Yb:CGA laser operating in the net normal or net anomalous dispersion region. With 26 W pump power, stable femtosecond laser pulses with average power of 4.5 W are obtained, yielding a pump power slope efficiency of 17%. Operating at 80.5 MHz repetition rate, the laser delivers as short as 93 fs pulse duration with average output power of 4.5 W, corresponding to a pulse energy of 56 nJ and a peak power of 0.59 MW. The oscillator exhibits a passive rms power stability of ~0.38% rms over 5 h in high beam quality.