Orientation-patterned gallium phosphide OPO developments for long-wave infrared lidar applications

In this paper, we describe picosecond, nonlinear optical experiments with Orientation-Patterned Gallium Phosphide (OPGaP) crystals as a precursor to the development of a solid-state Lidar that can operate in the Long Wave Infrared (LWIR) waveband (7.5-14 μm). An Optical Parametric Oscillator (OPO) is used to compare the performance of OPGaP fabricated on gallium phosphide versus a gallium arsenide substrate. Both materials provide a viable route to generate high peak power, short duration laser pulses in the LWIR waveband. We then demonstrate that OPGaP can be used for up-conversion from the LWIR into the silicon detector waveband. Finally, parametric generation in OPGaP with picosecond pulses is studied and we discuss how it can be used to generate a seed beam for a parametric amplifier.