The Research Of Optical Switch Design And Optical Devices Integration Based On Photonic Crystal

The realization of the future all optical networks, mostly depending on the all optical devices, such as high-speed light sources, all optical switches, all-optical wavelength converters, all optical buffers and so on. As the core devices of the optical packet-switched network, the best choice of future networks, all optical switches and all optical buffers have drawn a surge of research activities. However, how to integrate the optical devices in a chip will be another challenge in realizing the all optical network. Photonic crystal (PhC) could easily control the propagation of light, which can lead to the fabrication of high-performance devices. Moreover, fabrication of PhCs is now well controlled and the fabrication procedures are similar to those used to realize silicon integrated circuits. The PhCs have many good features, for example, the inhibition of spontaneous emission, small volume and easy to be integrated; so they can be used to design optical switch and slow light module with a lot of advantages.In this article, all optical switches based on one-dimensional and two-dimensional PhCs are analyzed and designed, using PhC nonlinear effect, which have stably controllable output. And this article analyzes the integration of all optical switch and slow light waveguide, and show the compound function of the integration device.First, the requirement for all optical switch and integration devices in the development of all optical networks is mentioned. And the research status of all optical switch and integration device, the advancement of using PhC to design the device and realize all optical integration are also introduced.Second, the study background and method of photonic crystals are mentioned, and the application of photonic crystal in optical communication is analyzed. This article analyzes the features and slow light method of two-dimensional PhC.Third, one all optical switch with multi-defects based on one-dimensional photonic crystal is designed using nonlinear Kerr effect, which has a board defect mode and a narrow defect mode, making the output of all optical switch can be stably controlled by the pump light. And, using the same method, one optical switch based on periodic dielectric waveguide is proposed, and this paper compares the different characters of the optical switch under the condition whether consider the thickness of medium.At last, a line-defect photonic crystal with a flattened band with low group velocity and vanishing Group Velocity Dispersion is designed. By setting the proper parameters of two structures, the signal channel of optical switch is in the flat band of slow light waveguide, so the signal can be slowed down by slow light waveguide after passing through the optical switch. In addition, proper connection structure of the joint is chosen, to make the signal light couple into the slow light waveguide from optical switch efficiently. Ultimately, light propagation in both the optical switch and the slow light structure is shown to demonstrate the compound function of the integrated device.