Research Of Graphene Electro-optical Ring Modulator On Silicon

Electro-optical modulator is an important device of optical communication systems.With the advantages of fast modulation rate,high extinction radio and low driving voltage,electro-optical modulator is widely used in optical transmitter module in optical communication systems.Graphene is a new type of material with excellent electrical and optical properties.Therefore electro-optical modulators based on grapheme have many unique advantages over traditional modulators,such as high modulation rate,small modulation size,low cost and good modulation effect.Silicon waveguide has some advantages,for example,low production cost,mature technology,easy system integration,and the ring resonator structure has characteristics such as high modulation sensitivity,small size,low bend loss and easy integration in traditional process.Therefore based on the mature technology of silicon waveguide and utilizing the structural advantages of ring resonator,graphene-based electro-optical ring modulator has a very broad research prospect.The main content of this paper is about graphene electro-optical ring modulator.Based on the basic properties of graphene and the working principle of ring resonator,the influence of various parameters of the ring resonator on the performance parameters of electro-optical modulation is studied.The influence of the properties of graphene itself on the performance of modulator is also studied in this paper.And graphene electro-optical ring modulator is designed.The main contents of this paper are as follows:First of all,the research background of this paper and the research status of electro-optical modulator and graphene at home and abroad are expatiated,and then the content of this paper is summarized.The development of graphene and preparation methods,as well as a variety of graphene excellent electrical and optical properties is discussed.The trend of graphene conductivity and effective refractive index changed with Fermi level is analyzed and simulated by MATLAB.Secondly,the basic structure and working principle of ring resonator are discussed,the theoretical model of the ring resonator is established,and the influence of the structure parameters of the ring resonator on its performance is analyzed.Analysis shows that adding graphene material,changing device parameters will make ring resonator transmittance curve biased.The working mode of electro-optical modulator and the change of structural parameters on the performance of modulator is studied when the ring resonator structure is applied to the electro-optical modulator.Analysis shows that the choice of structural parameters,such as the radius of the ring resonator will affect both Q and FSR,so it should be considered to choose the right parameter.The advantages of multi-ring serial structure and parallel structure are discussed,the theoretical model is established,and the structure is optimized according to the simulation results.Finally,the performance of electro-optical modulator optimized by the structural parameters is analyzed and simulated,and the performance of the electro-optical modulator is analyzed,such as extinction radio and driving voltage.The light field distribution and the effective refractive index in different modes of graphene are simulated.Different structure of electro-optical modulator is designed and its performance is analyzed and compared.