L2 DUHA (Dual-beam Ultra-fast High energy OPCPA Amplifier) will be a source of 100 TW pulses with a repetition rate 20 Hz (50 Hz in future) and a central wavelength 820 nm and is currently being developed in the Extreme Light Infrastructure ERIC as one of its four main beamlines. The L2 DUHA will be predominantly used for laser wakefield acceleration.

The main topic of this seminar is the overall description and current status of L2 DUHA’s main pump laser. It consists of a laser diode with a distributive feedback used as the primary source and a cascade of four amplifiers. The last one is a cryogenically cooled, diode-pumped Yb:YAG amplifier generating 12 J pulses at 1030 nm.