Research On Integrated Devices Of Photonic Crystal Electro-optic Modulation And Wavelength Division Multiplexing

With the further development of the Internet era,people's demands for the capacity and speed of the communication system is increasing.At present,the technology of single-function device has been basically mature.The only way to realize the communication system toward "high speed","large capacity","low power consumption" and "small size" is silicon-based optoelectronic integration.Silicon-based optoelectronic integrated devices can be compatible with CMOS technology.Moreover,it is a device with low processing cost,small size,and high integration.Electro-optic modulator and wavelength division multiplexer are important components in modern optical communication system.Therefore,the research on the integration of silicon-based electro-optic modulator and wavelength division multiplexer has important application value.In this paper,two kinds of integrated devices based on photonic crystal dual channel electro-optic modulation and wavelength division multiplexing are proposed.One is an electro-optic modulator module and a wavelength division multiplexer module that both use the combination of an L3 cavity and a silicon-based photonic crystal waveguide,which successively realize the functions of electro-optic modulation and wavelength division multiplexing with a wavelength interval of 20 nm.Through the design and optimization of the integrated device,the corresponding simulation results at the wavelength of 1530 nm and 1550 nm are: the insertion loss is0.65 d B and 0.68 d B,the extinction ratio is 21.02 d B and 22.33 d B,the modulation depth is 0.99,and the channel crosstalk is-29.07 d B and-27.62 d B respectively,the modulation rate is about 16.67 GHz,and the device size is only 17.83 um × 17.3um × 0.22 um.In order to further shorten the wavelength interval and expand the channel capacity,another structure is proposed,which adopts the combination design of one-dimensional photonic crystal nanobeam and nanowire waveguide to realize the electro-optic modulation and wavelength division multiplexing functions with the wavelength spacing of 3.2 nm.The simulation results show that the insertion loss is 0.89 d B and0.40 d B at 1550.4nm and 1553.6nm,the extinction ratio is 17.13 d B and 22.52 d B,the modulation depth is 0.98 and 0.99,the channel crosstalk is-24.20 d B and-23.37 d B respectively,the modulation rate is about 12.5 GHz,and the device size is only 71.34um×7.8um×0.22 um.These two integrated devices have excellent performance,compact structure,easy integration,and can be applied to CWDM high-speed optical communication systems.