High-energy, diode-pumped, nanosecond Yb: YAG MOPA system

Diode-pumped nanosecond multi-pass laser amplification to the joule level using an Yb: YAG slab crystal has been demonstrated. A maximum output pulse energy of 2.9 J at an optical- to-optical efficiency of 10% has been achieved. The seed pulses with a pulse duration of 6.4 ns were generated in a Q-switched Yb: YAG laser and amplified up to a pulse energy of 200mJ in a multi-pass booster amplifier. A maximum average output power of 15W at a repetition rate of 10 Hz has been measured. We also present a relay imaging semi-stable cavity for multi-pass amplification and a diode-pumping scheme employing horizontally stacked high-power laser diodes. (c) 2008 Optical Society of America.