A process to form a periodically poled polymer film by photoisomerization is described. A poled film of polymethylmetaclyrate containing 5 wt % of 4-(4-nitrophenylazo)aniline (Disperse Orange 3) was exposed to an Ar+ laser beam using a photomask of a 100 μm period grating. Disorientation of the chromophore molecule resulted in decrease of d33 in the photoisomerized domain. Quasiphase-matched second-harmonic generation is demonstrated experimentally using a processed film. Phase-matching was confirmed by tuning the fundamental wavelength around 1200 nm. The effective propagation length due to a tightly focused fundamental wave and the influence of the absorption loss are discussed. The depoling process by photoisomerization is compared with photobleaching, optical poling, and electron beam treatment.
ASJC Scopus subject areas
- Physics and Astronomy(all)