Linear and non-linear gratings in DR1 side chain polymers

Linear (refractive index) and non-linear (second order non-linear optical s usceptibility) gratings are of primary interest in optoelectronics. While l inear gratings may be used for filtering or wave length selective coupling, non-linear gratings may find applications in active devices such as second harmonic generators, parametric generators or all optical switches through cascading of second order susceptibilities. We report on a simple method f or the inscription of linear or non-linear gratings in DR1 side chain polym er thin films or waveguides. The technique is based on the photoisomerisati on induced reorientation properties of such a material under irradiation wi th an argon ion laser. It avoids the use of interdigited electrodes for the selective orientation of the dyes, can be easily applied to a waveguide ge ometry and results into a good orientational stability. Sample characteriza tion involves polarized microscopy and second harmonic generation. (C) 1999 Elsevier Science B.V. All rights reserved.