Study On The Electro-optic Coefficient Measurement Of Polymer Materials And Its Application

Polymer materials are characterized by low dielectric coefficient, easy fabrication process, compatibility to integrated techniques and attract wide attentions. Electro-optic (EO) polymers possess high nonlinear coefficients and have great prospect in the field of integrated optics especially in optical communication devices. Good EO materials can be used to fabricate optical communication devices such as high speed optical switches, tunable filter and wide band optical modulators.This thesis first gives a simple review of the basic principles of nonlinear optics and the EO effect including the theory about nonlinear optic polarizability, EO effect and EO coefficients, relationship of the EO coefficients and 2nd order nonlinear optic coefficient and so on. Meanwhile the poling process which is used to enhance the EO effect of polymers is introduced.Then the thesis focuses on the EO coefficient measurement of the poled polymers. First, the method based on ATR technique to measure the EO coefficients under the wavelength of 632.8nm is discussed. Then EO coefficient measurement of poled polymer thin films based on fiber-optic Michelson interferometer is presented which can measure the EO coefficient of the poled polymer thin films under the optical communication wavelength of 1550nm. The dissertation discusses the measurement principles in details and discusses the system stability and sensitivity. And also presented in the thesis are some measurement results.In the final section, the application of EO polymers in novel photoelectronic devices is explored. The polymer covered long period fiber grating and waveguide grating based on electro-optical tuning are suggested. Analysis of this structure is given and the fabrication process is discussed.