Water-cooled thin disk Ti:Sapphire amplifiers for kW average power

Rapid development of ultrafast laser systems led to the generation of laser pulses with several PW peak power in table top arrangements [1]. Most of these systems rely on amplification using Ti:Sapphire (Ti:Sa), which has exceptional spectral and thermal properties [2]. Reaching ultrahigh peak power pulses at high repetition rates, which is favorable for many applications, is however still a great challange due to the thermal load in the gain medium. By using conventional cooling techniques non-uniform transverse temperature profile is created in the crystal, which leads to serious beam degradation during the amplification process. Thin disk (TD) technology may offer the possibility for Ti:Sa crystals to be used in with high average output power systems. Research and development has strongly focused on relatively narrow emission spectral band media (doped YAGs) and thus the pulse duration has been limited to the lower, sub-picosecond regime [3].