Optical And Acoustic Sensing Properties Of Graphene-slot Cascade Microcavities

In the information age of the 21st century,technologies such as information acquisition,processing,storage and transmission have received extensive attention.With the maturity of the manufacturing process of micro-nano-optical integrated devices,micro-ring resonators have become a hot device in current research due to their small size and low loss.They are used in various fields such as optical filtering,sensing,acousto-optic modulation,and detection.Has been widely used.However,changing the structure of the basic micro-ring resonator and analyzing its response to physical fields such as light and sound fields have great research significance for improving the performance of the system.Based on the optical and acoustic properties of the micro-ring resonator,this paper first analyzes the optical transmission characteristics of the micro-ring resonator,and then introduces the graphene material to change the slot-based wave-guide double micro-ring system.The structure implements optical sensing and modulation functions,and then uses the cantilever structure to test the acoustic characteristics of the system to complete the acousto-optic modulation.The main contents including:In the first chapter,we introduced the relevant content of the micro-ring resonator,and introduced the design ideas and applications of the micro-ring resonator when it is covered with graphene materials and when it is applied to hydrophones.Finally,the finite difference time domain method(FDTD)and multiphysics simulation software(COMSOL)are introduced.In the second chapter,based on Maxwell's electromagnetic field theory and coupling mode theory,we analyzed and deduced the transmission characteristics of single wave-guide single-ring and single wave-guide double micro-ring structures,respectively.The theory and calculation methods of finite difference time domain method and simulation are explained,and the basic theory of graphene materials is briefly introduced.In the third chapter,we covered the graphene material on the microring resonator and studied its effect on the system.Among them,the influence of the position and length of graphene,the properties of graphene itself,and the environmental temperature on the system to varying degrees were studied.It laid the foundation for the next analysis of the system structure with graphene added.In the forth chapter,we obtained the sensing performance of the graphene-slit double micro-ring structure photoelectric modulator through simulation calculations.Then we simulated the optical transmission characteristics of the micro-ring resonator after inserting the graphene and we observed its performance Variety.We respectively calculated the change law of the transmission spectrum of the system covered with graphene at different feature positions and simulated and tested the optical sensing characteristics of the system when the device was placed in a water environment.In the fifth chapter,we analyzed the acoustic sensing characteristics of the micro-ring resonator and the elastic-optical effect of the material.The micro-ring resonator is combined with the cantilever arm structure,and the detection of the deformation degree of the system is completed through three-dimensional simulation.The mode field distribution and sound pressure distribution of the transmission spectrum are obtained by two-dimensional simulation,and the change of the effective mode refractive index of the material caused by the change of the sound field angle and position is further calculated and numerical simulation for a microring resonator in the form of a four-ring array.In the last chapter,we summarized the characteristics of the structure proposed in this paper,and summarized and prospected the research work of hydrophone applications based on micro-ring resonators.