Near diffraction limited pulses with 52-mJ, 1.2 ns at 0.5 kHz, generated by Nd-based MOPA

摘要

Reliable high-energy (>10 mJ) laser systems with high-peak power (>10MW) pulses at kHz repetition rates, having diffraction-limited beams are highly desirable for a number of industrial, military and scientific applications, e.g. chemical sensing, various LIDAR, materials synthesis and processing, highly efficient nonlinear frequency conversion, etc. However, in the vast majority of kHz ns-laser systems the output pulse energy is below few tenths of mJ whilst, the repetition rate of the presently existing high pulse-energy systems does not exceed 50–100 Hz and are far from single TEM00 mode. In this work, we report the amplification of laser pulses from a near diffraction limited, passively Q-switched Nd:YAG master oscillator (0.58 mJ, 1.2 ns at 0.5 kHz) up to 52-mJ in a Nd:YVO4 preamplifier and two diode pumped boost YAG-amplifiers, whilst preserving pulse duration, beam quality and linear polarization.