All-optical Spectral Quantization Scheme Based On Based On Cascaded Chalcogenide-silicon Slot

Analog to digital converter(ADC)as a key interface technology between the real world and current digital technologies has been extensively applied to many signal processing systems,such as radar systems,software radio,medical imaging,and communication systems.However,uncertainty in the sampling instant due to aperture jitter has been a major bottleneck on the way towards speeds and better accuracy.Optical Photonic analog-to-digital conversion technology is considered as the competitive candidate to overcome the electronic bottleneck.The previous proposed scheme includes phase encoding quantization scheme,modulated electrode optical coupling scheme,multi-period transfer functions,phase-shifted quantization using electro-optic modulators and interference and spectral quantization using optical nonlinear effects.Among the schemes based on spectral quantization using optical nonlinear effects,the soliton self-frequency shift(SSFS)effect can directly establish the linear relationship between the wavelength shift and the input peak power.However most of the previous proposed scheme based on SSFS always uses the long distance fiber as the main waveguides,which is hard to be integrated.This thesis will mainly talk about the application of silicon slot waveguides in the all-optical quantization scheme.In this thesis,we mainly introduce the development history and implementation scheme of analog-to-digital converter and emphasizes the quantization scheme based on self soliton frequency shift and the method on the improvement of quantization resolution.We started with the Maxwell equation to deuct the Generalizes Nonlinear Schrodinger equation and introduced two numerical method to solve this nonlinear equation,namely split-step fourier and Runge-Kutta method and dispersion effect and nonlinear effect in the optical waveguides.Hence,based of photonic technologies we compared the advatanges and disadvantages of chalcogenide-silicon slot waveguides with traditional SOI on their performance and manufacture and presents four basic structure of silicon slot waveguides in detail.Therefore we propose a novel all-optical spectral quantization scheme based on soliton self-frequency shift(SSFS)effect in two chalcogenide-silicon slot waveguides(CSSW)with different structures,in which the latter CSSW is responsible for introducing the spectrum compression.And the spectrum width of the final quantized pulse can be compressed to under 13nm.The quantization results show that the effective number of bit(ENOB)can be increased to 5-bit compared with the scheme without the process of spectral compression.