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arXiv · 2012.15119

Frequency-doubled Nd:YAG MOPA laser system with programmable rectangular pulses up to 200 microseconds

Maximilian Beyer·Jack C. Roth·Eustace Edwards·David DeMille
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Abstract

A compact frequency-doubled diode-pumped Nd:YAG master-oscillator power-amplifier laser system with programmable microsecond pulse length has been developed. Analog pulse shaping of the output from a single-frequency continuous-wave Nd:YAG oscillator, and subsequent amplification, allowed the generation of rectangular pulses with pulse lengths on the order of the Nd:YAG fluorescence lifetime. Temporally flat-top pulses of 1064 nm light with 520 mJ pulse energy, 2.6 kW peak power, and 200 $\mu$s duration, with linewidth below 10 kHz, were obtained at a repetition rate of 2 Hz. Second harmonic generation in a LBO crystal yielded pulses of 262 mJ and 1.3 kW peak power at 532 nm. The peak power can be maintained within 2.9% over the duration of the laser pulse, and long-term intensity stability of 1.1% was observed. The spatially flat-top beam at 1064 nm used in the amplifier is converted to a Gaussian beam at 532 nm with beam quality factor $M^2=1.41(14)$ during the second harmonic generation. This system has potential as a pump source for Ti:sapphire, dye, or optical parametric amplifiers to generate tunable high-power single-frequency radiation for applications in precision measurements and laser slowing.

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Maximilian Beyer, Jack C. Roth, Eustace Edwards, David DeMille. 2020-12-30. Frequency-doubled Nd:YAG MOPA laser system with programmable rectangular pulses up to 200 microseconds. https://doi.org/10.1364/oe.427832

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