Study On Wavelength Conversion And Phase Sensitive Parametric Amplification In Silicon Waveguides

With the requirement of the information transmission rate and transmission capacity higher and higher,people are not satisfied with the ability of the traditional electrical communication in terms of transmission rate and bandwidth.All optical communication is a good solution to the limited transmission rate and bandwidth.All optical wavelength conversion and phase sensitive parametric amplification that based on four-wave mixing(FWM)have promoted the development of all optical communication.As a nonlinear effect of all optical signal processing,FWM has been studied intensively and been widely used in the optical fiber.However,the small nonlinear Kerr coefficient and refractive index difference of optical fibers result that it needs hundreds of meters of fiber to generate FWM for wavelength conversion and phase sensitive parametric amplification,which restricts the development of the optical communication system on chip.Silicon waveguides are adaptive to the development of integrated optics for its high nonlinear coefficient,small size and low loss.Besides,the manufacturing process of silicon waveguides is becoming mature.Therefore,silicon waveguides are gradually becoming an ideal platform to achieve wavelength conversion and phase sensitive parametric amplification and has a good application prospects in the field of optical communication on chip.In this paper,the main work is wavelength conversion and phase sensitive parametric amplification that based on FWM effects in silicon based waveguides.The main contents are as follows:1.The research background of silicon waveguides was discussed.The common structures of silicon waveguides were compared and the main three order nonlinear effects in silicon waveguides were analyzed.We also introduced the development and present situation of FWM effect.2.Nonlinear Schrodinger equation for optical transmission in silicon waveguide was discussed.The coupling wave equations of FWM effect were analyzed based on the theory of optical transmission.The theoretical results show that efficient FWM can be obtained when the phase mismatch is zero,and the phase matching condition can be realized by adjusting the waveguide dispersion or using the quasi-phase matching technique.3.A slot width changing slot waveguide was designed by using quasi phase matching technique,and it was used to research on wavelength conversion.The design method of waveguide was expounded in detail.Quasi-phase matching can be achieved by optimizing waveguide structure.The simulation results show that high efficiency wavelength conversion can be realized in the waveguide.The maximum conversion efficiency was 11.32 dB and conversion bandwidth was 570 nm which was 123 nm higher than that in waveguide with constant slot width.4.A horizontal slot waveguide full of silicon nitride was proposed to analyze phase sensitive amplification.The waveguide dispersion was optimized.A phase-extinction ratio of 29 dB was achieved by solving the modified nonlinear Schrodinger equations.The input signal power and linear loss of waveguide has less effect on phase-extinction ratio.