cw harmonic generation in the uv using a thin-film waveguide on a nonlinear substrate

Abstract

Phase-matched second harmonic in the thin-film and nonlinear Cerenkov radiation in the substrate have both been observed in the uv on a cw basis in a thin-film waveguide structure consisting of an aluminium-oxide film deposited on a quartz substrate. A sharp resonance in the second-harmonic output was observed as the fundamental wavelength was tuned through the phase-matching point. In contrast, the Cerenkov radiation was found to be broadly and continuously tunable and relatively intense.