Organic Polymer Electro-optic Modulator Design And Experimental Study

Optical intensity modulator based on Mach-Zehnder waveguide is an important device of Integrated Optics and plays an important role in the field of civilian use, defense,and scientific research.Nonlinear organic E-O polymer has a high E-O coefficient,low fabrication difficulty,compatibility with semiconductor techniques, small dispersion in infrared to millimeter band,fast response and is therefore regarded as an important driving force for the development of integrated optical device. Mach-Zehnder(M-Z) E-O intensity modulator based on nonlinear E-O polymer waveguides is an attractrive research area for many countries.The current development and the prospect of polymer-waveguide-based devises were introduced at first.Then the theory,fabrication techniques and measurement methods were studied systematically.The major processing steps of polymer waveguide were studied.The sub-electrode is deposited with the vacuum thermal evaporation technique;the lower cladding layer was obtained by spin-casting;the polling system for polymer thin film was used and experiments are conducted on the sample of the host-guest system of a novel chromophore DCDHF-2-V and PMMA;the Reactive Ion Etch for processing the lower cladding was studied preliminarily and results were obtained with surface profilometry. These works give a solid foundation for the final realization of the prototype of polymer waveguide M-Z modulator.A numerical method based on the Taylor Series Expansion method was optimized by two methods,realized and will be applied to a real design.The fundamental TM mode distribution in the M-Z modulator with various parameters was analysied,and the optimized result based on the minimum optical power loss was obtained. Two-dimensional simulation employing Padémethod was also realized and the results of the two methods were compared.By expanding the Padémethod to 3-dimension case, the distribution of the fundamental TM mode of the cross section was obtained and a direct view of how the optical power caused by the mode mismatch is lost in the propagation was also obtained. A system for measuring the E-O coefficient based on the Simple Reflection Method is used to test a polled sample.However,the result was much lower than the reported value,therefore,the possible cause of the difference was analyzed;a waveguide sample is tested with the Prism Coupling Method and the refractive index and thickness is solved numerically using a program designed with Matlab.