GRATING-ENHANCED 2ND-HARMONIC GENERATION IN POLYMER WAVE-GUIDES - ROLE OF LOSSES

A numerical study of second-harmonic (SH) generation in a corrugated p olymer waveguide is performed with a rigorous electromagnetic theory. Comparison with experiment reveals the role of losses inside the waveg uide-small losses do not significantly affect the nonresonant response and reduce the resonant enhancement of SH generation. High losses can lead to the opposite effect-instead of enhancement, dips in the SH ef ficiency are observed in the vicinity of guided-wave excitation. The p eculiarities of the angular dependencies of SH generation are explaine d from the phenomenological point of view, and the role of phase match ing is discussed.