Integrated electro-optical waveguide based devices with liquid crystals on a silicon Backplane

Special liquid crystal blends having properties such as large EO Kerr constants, low optical loss and sub-micro-second response time are used in a new concept of integrated field-induced optical waveguides. Based on these waveguides, with an appropriate chip design configuration including a special arrangement of electrodes, a variety of single-mode and also multi-mode variable devices can be obtained. The fabrication is realized on a silicon backplane by means of bulk micro-machining processes. Particularly low loss, microsecond, polarization insensitive switching as well as variable power splitting could be demonstrated. These devices were designed for operation at the 1.55 µm telecommunication wavelength. Nonetheless, configurations optimized at any wavelength within VIS to IR range are possible. These devices feature compactness, integrability, and scalability. The new waveguide concept enables the possibility of dynamic, continuously voltage controlled adjustment of optical signals transmitted in fiber optic networks and find important applications in present and future telecommunication and fiber optic sensor networks.