Max Planck Institute of Quantum Optics 1 article published in JoVE Bioengineering 20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier Ayman Alismail1,2, Haochuan Wang1,3, Jonathan Brons3, Hanieh Fattahi1,3 1Department of Physics, Ludwig Maximilian University of Munich, 2Physics and Astronomy Department, King Saud University, 3Max Planck Institute of Quantum Optics A protocol for the operation of a high-energy, high-power optical parametric chirped pulse amplifier pump source based on an Yb:YAG thin-disk regenerative amplifier is presented here.