Nonlinear Optical Processes in Polymer Films.

Abstract

Abstract : Electrooptic organic polymer thin films show great promise for applications in integrated optoelectronic devices. These materials are usually formed as guest-host polymer systems that exhibit large second order nonlinear optical coefficients, low DC and microwave dielectric constants, and broad optical transparency ranges. The major obstacle to the development of practical polymer optoelectronic devices has been the thermal stability of the electrooptic coefficients of the guest-host polymer films. Current research has focused on finding new guest dye chromophores that possess large nonlinear optical coefficients and thermal stabilities greater than 300 degrees. We summarize our recent development of a new class of high thermal stability fused-ring chromophores, l,8-naphthoylene benzimidazoles, based on compute aided molecular design and experimental measurements of microscopic second order optical coefficients. The new chromophores were designed for their structural similarity to polyimide repeat units and consequent easy incorporation into high temperature host polyimides. They are highly colored, comparatively soluble in common organic solvents, and very stable in polyamic acid solutions. They possess relatively large second order optical coefficients and thermal stabilities exceeding 340 degrees. (MM)