Exploiting nonlinear spectral broadening in a 400 W Yb:YAG thin-disk multipass amplifier to achieve 2 mJ pulses with sub-150 fs duration. Optics Communications, (429):180--188, Elsevier BV, December 2018. [PUMA: YbYAG myown peer Modelocked PulseCompression Diodepumped thindisklaser MultipassAmplifier Ultrafast diodepumped] URL