High-power femtosecond Yb:YAG laser based on a power-scalable concept

Abstract

We demonstrate a power-scalable concept for femtosecond lasers with very high average powers. It is based on a thin disk Yb:YAG laser [1], passively mode-locked with a semiconductor saturable absorber mirror (SESAM) [2, 3]. In a first step, we obtained 16.2 W of average power in pulses with 730 fs duration, 0.47 μJ energy, and 560 kW peak power (Fig. 1). This is to our knowledge the highest average power reported for a laser oscillator in the sub­picosecond regime, and we expect even significantly higher powers to be possible in the near future. The repetition rate is 34.6 MHz and the beam quality is close to diffraction-limited (M2 < 1.5). Such lasers are interesting for numerous applications, e.g. for synchronously pumping high-power optical parametrical oscillators in RGB laser displays.