Design and fabrication of nonlinear optical polymer waveguide devices

Issues related to the design of poled electro-optic polymer waveguide have been analyzed in terms of modulation voltage, optical loss due to metal electrode and mode size. The analysis suggests a c,ouple of general guidelines for the device fabrication. Firstly, asymmetric structure gives better performance than symmetric structure in term of modulation voltage and mode size, where the refractive index of one of the buffer layers is close to the guiding layer and that of the other layer is much smaller than the guiding layer, by more than 0.1. Secondly, the guiding layer needs to be fabricated as thick as possible within the range of the single mode operation for a given material system to obtain lowest possible modulation voltage under a given limit of electrode associated loss. Electro-optic modulators fabricated using the photobleaching technique supported the guidelines.