Abstract

We present a new concept which allows to build femtosecond lasers with very high average output powers. It is based on a thin disk YbzYAG laser [1], passively mode-locked with a semiconductor saturable absorber mirror (SESAM) (Fig. 1). In a first step, we obtained 16 W of average power in near transform-limited soliton pulses (Fig. 2) with 730 fs duration, 0.47 μJ energy, 560 kW peak power, and near diffraction-limited beam quality. Damage of the SESAM is not observed, and Q-switching instabilities are suppressed at full output power. The average power of 16 W is to our knowledge by far the highest reported for a laser oscillator in the sub­picosecond regime, and we are working towards even significantly higher powers. Such lasers are interesting for numerous applications, e g. for synchronously pumping high-power optical parametrical oscillators in RGB laser displays.

© 2000 IEEE