High-efficiency 2 J, 20 Hz diode-pumped Nd:YAG active-mirror master oscillator power amplifier system

Abstract

A high-efficiency joule-class diode-pumped Nd:YAG active-mirror amplifier was demonstrated. By using four elastically held Nd:YAG slabs as the active medium, we achieved a stable operation with an output pulse energy of 2.3 J at a repetition rate of 10 Hz (2.1 J at 20 Hz) in a 15 ns pulse in two-pass extraction geometry from a four-stage amplifier, corresponding to an optical-to-optical conversion efficiency of 36% for the overall laser system. To the best of our knowledge, this is the highest efficiency from a joule-class diode-pumped laser system ever reported.