Study On All-Optical Wavelength Conversion Based On Silicon Waveguide

All-optical wavelength converter is a key device in optical switching network and can be achieved by the nonlinear effects. As a key element of the WDM optical network, it is a hotspot in actual research. The all-optical wavelength conversion technology based on the four-wave mixing (FWM) can be strictly transparent to the frequency and phase of the signal and it results in the independence between the wavelength conversion and the form of the signal. It will have a good prospect for development in the future. Silicon-on-insulator (SOI) waveguide is a new-type optical electronics material based on silicon and the non linear effect of the Raman and Kerr in the SOI waveguide is higher by a factor of about 1,000 and 200 respectively than that of conventional single-mode in optical communication band. It can achieve strong light confinement and large effective nonlinearity due to its high refractive-index contrast between the silicon core and silica cladding. A wide variety of nonlinear optical phenomena will occur in the condition of low power and short waveguide. Consequently, it can realize the nonlinear functional devices which possessing the low-power, high bandwidth, high-speed, low-cost and on-chip characteristics.The paper focuses on the wavelength conversion based on FWM in SOI waveguide, and includes several aspects as follows.The characteristics of SOI waveguide and correlative optical waveguide devices based on silicon are introduced. It is analyzed that the theory of FWM equations in SOI waveguide and the phase should be matched in FWM. The factors affecting the FWM and how they affect are discussed.Based on the simulation of the wavelength conversion in the SOI waveguide, the influences of dispersion, input pump power, free carrier lifetime and waveguide length on the conversion efficiency and noise are discussed. The results indicate that the conversion efficiency isn't a simple linear relationship with the pump power and the noise figure values decrease at first but then begin to increase with the increasing the pump power. The free carrier lifetime has a great impact on the conversion efficiency and noise figure so it should be reduced. The choice of the waveguide length should be determined by the actual needs.Finally, a summary of the paper is given as well as the prospective of the research.