Study On The Fano Resonance Characteristics Of The MIM Waveguide Coupling Cavity Based On SPPs

With the rapid development of electronic information technology,traditional electronic devices can not satisfy the storage and transmission of large amounts of data on the size and performance.The optoelectronic devices shows obvious advantages in parallel processing,storage,anti-interference transmission and transmission rate for large amounts of data.So it has become the focus of the researchers.Surface plasmon polaritons(SPPs)are electromagnetic waves propagating along the surface of metals and electrolytes.They are an electromagnetic oscillation mode caused by the interaction of incident photons and electrons on metal surfaces.Therefore,micro-nano optoelectronic devices based on surface plasmon have been rapidly developed and widely used in sensors,nanosensors,beam splitters,filters and multi-channel output selectors.In this paper,the optical properties and dispersion relations of surface plasmon are explained.The properties of nanomaterial graphene and the current research status are introduced.Then a metal-insulator-metal(MIM)waveguide structure consisting of a baffle and an M-cavity is designed to generate the dual Fano resonance,which is observed by changing the structural parameters of the coupling side cavity and the refractive index of the medium.The controllable adjustment of the fano resonance spectrum peak is realized,and has very good flexibility in structural design and adjustment.The simulation results show that the sensitivity of the structure reaches 760nm/RIU,and the maximum figure of merit is 9.9×10~4.The improved symmetrical M-waveguide structure is obtained through further simulation calculation.The maximum figure of merit is 1.56×10~5,and the performance is further improved.The structure may have application value in the field of biosensing.Finally,a MIM waveguide structure consisting of a work-type side coupling cavity and a baffle is proposed to generate Fano resonance.Then transmission spectrum of the Fano resonance is analyzed from the structure,the phase and the steady-state magnetic field.Then the structural parameters are changed to observe the influence on the transmission spectrum.The simulation results show that the sensitivity of the structure reaches 1280 nm/RIU.Then,the nano-material graphene is added in the MIM waveguide structure.The waveguide structure has about 23%improvement in transmission performance.Therefore,it has wide application prospect in the design of highly integrated circuits and nano sensors.