240-fs pulses with 22-W average power from a mode-locked thin-disk Yb:KY(WO_4)_2 laser

Abstract

We demonstrate what is to our knowledge the first passively mode-locked thin-disk $\mathrm{Yb}:\mathrm{KY}{\left({\mathrm{WO}}_4\right)}_2$ laser. The laser produces pulses of 240-fs duration with an average power of 22 W at a center wavelength of 1028 nm. At a pulse repetition rate of 25 MHz, the pulse energy is $0.9 \mathit{\mu }\mathrm{J}$, and the peak power is as high as 3.3 MW. The beam quality is very close to the diffraction limit, with $M^2=1.1$.