Abstract

Nonlinear organic polymers are promising materials for optical and electrooptic devices. Efficient frequency conversion using their high intrinsic nonlinearity is one application of these substances. We have achieved phase-matched second-harmonic generation (SHG) by incorporating a periodic structure into a planar, linear waveguide configuration. Rather than applying a periodically domain-inverted nonlinear waveguide (Fig. la), we have used a lossless linear commercial waveguide, topped with a periodically structured, nonlinear adsorbate (Fig. 1b). To facilitate the in-situ fabrication of the grating structure by laser ablation a thin film of 100 nm thickness, prepared from a PMMA-chloroform solution with addition of a hemicyanine dye of high second-order nonlinearity, ^[1] served as adsorbate.

© 1992 IQEC