Research On Electro-optic Modulator Based On Photonic Crystal Resonator With Wavy PN Junction

With the rapid development of data communication industry,people urgently hope that the signal transmission speed of optical communication system is higher and the transmission cost is lower.As a key device in the optical communication system,the electro-optic modulator with high modulation rate,low driving voltage and low insertion loss can effectively improve the transmission quality of the optical communication system.Photonic crystal has been widely concerned because of its superior material properties.Therefore,it is of great value to study the photonic crystal electro-optic modulator.In this thesis,an electro-optic modulator based on photonic crystal wavy PN junction is proposed.In the modulator,a hexagonal optical resonator is introduced into the two-dimensional photonic crystal,p and n dopants of different concentrations are added to the resonator to introduce a wavy PN junction.The flat electrode adopts a reverse bias voltage,and the"on"and"off"modulation of the incident light is realized by applying different voltages on both sides of the flat plate of the photonic crystal,which is simulated by using lumerical FDTD solutions module and Device module of the real software build the simulation model of the device respectively,and analyze the influencing factors of the device performance according to the simulation results.Then,by changing the wave height and period of the wavy PN junction,the modulation rate,driving voltage and insertion loss of the device are observed.The results show that when the applied voltage is 0 V and 1.04 V respectively,the effective refractive index difference can reach 0.002,and the narrow bandwidth"on"and"off"modulation of TE mode with the central wavelength of 1584.5nm can be realized.The modulation rate can reach 8 GHz,the driving voltage is only 1.04 V,the extinction ratio is as high as 30.8 d B,the insertion loss is only 0.5 d B,and the Q value is as high as1.4×10~4.The modulator studied in this thesis has important significance and potential application value for high-speed optical communication system.