Diode-pumped Yb:LuAG and Yb:YAG disk laser amplifiers with high pulse energies

Ytterbium-doped garnets are attractive for use in high-energy diode-pumped solid-state lasers due to their spectral and thermal properties. Recently, Yb:LuAG was investigated as a promising candidate for kW thin-disk lasers because of its superior thermal conductivity especially at high doping concentrations compared to Yb:YAG. In this paper we demonstrate high-energy ns-pulse multipass amplification in Yb:YAG and Yb:LuAG towards 500mJ. The study presented here has confirmed that further scaling of both efficiency and pulse energy is possible by a further reduction of Yb-doping level reducing the gain per disk.