Optics Express
2015
16884–16889
, We report on a high power ultrashort pulse regenerative amplifier system, entirely based on thulium-doped laser materials operating around 1.94 \textgreekmm. At a repetition rate of 1 kHz the Tm:YAP regenerative amplifier emits pulse energies \textgreater 700 \textgreekmJ, only limited by the damage threshold of the Tm:YAP crystal. The pulses can be compressed to 380 fs at an efficiency of 50 %. Purging of the regenerative amplifier cavity with nitrogen is necessary due to atmospheric absorptions causing long ps pedestals in the autocorrelation.
DOI: 10.1364/OE.23.016884