The field of electro-optic (EO) polymer materials for integrated optics has been developing rapidly during the past several years. Recent advances include the formulation of poled crosslinked epoxies and guest-host polyimides exhibiting thermal stability at temperatures significantly higher than that previously achieved with thermoplastic acrylate chemistry. These developments are an essential first step toward achieving practical materials exhibiting stability to manufacture, assembly, and end-use in modern electronic systems applications.
Despite these developments, there is still much basic research to be performed to achieve a practical EO polymer material system. A polymer material system for integrated optics consists of a set of three compatible materials: cladding polymers, passive core polymers, and active core polymers. The three materials should ideally be derived from the same base polymer so that the layers of the entire waveguide structure have nearly identical thermal, mechanical, chemical, electrical, and optical properties. In an ideal syst', the active core material would consist of passive materials highly loaded with aligned nonlinear optical moieties exhibiting large hyperpolarizabilities and suitable size and shape for thermal stability.
This paper provides a detailed review of the material requirements for EO polymer waveguide devices in electronic systems and points to new areas of research required for practical systems.