Pulsed high peak power millimeter wave generation via difference frequency generation using periodically poled lithium niobate

We successfully demonstrated pulsed high-peak-power millimeter wave generation using periodically poled lithium niobate (PPLN) under collinear phase matching. We fabricated 0.5-mm-thick PPLN with a 40 mm interaction length for generating 250 and 300 GHz waves. Pump waves with very close dual wavelength output from a KTiOPO₄ (KTP) optical parametric oscillator had a pulse energy of 2 mJ, pulse duration of 15 ns, and wavelength around 1300nm. Millimeter waves were generated successfully, and the highest peak power obtained was estimated to be about 0.1 mW. This value is sufficiently high for envelope detection using a Schottky barrier diode. An active imaging system in the millimeter wave range could be realized using such a pulsed emitter and a Schottky barrier diode array.