Optical Parametric Amplifier At 1572nm Wavelength Using Ktioaso4 Crystal

We report on a nanosecond master oscillator /power amplifier architecture for optical parametric conversion of high pulse energy from 1.064 mu m to 1.572 mu m in KTiOAsO4 crystal. The signal emission is amplified by two different parametric amplifier architectures respectively. By comparing the results obtained, a novel amplifier architecture is chosen which is expected to combine the high gain and good beam quality. With a seeding signal energy of 1 mJ, and 400mJ pump pulse at 100Hz, a gain up to 64 at 1.57 mu m with the beam quality M-2 less than 4.8 is realized. The total optical-optical conversion efficiency reached 16%.