Study On The Structural Design And Transimission Characteristics Analysis Of The Novel MIM Filter Based On Surface Plasmon Polaritons

With the development of current information communication technologies,integrated circuits are also developing toward higher integration.Traditional optoelectronic devices have been unable to meet the increasing demand for high-speed information transmission.People are gradually exploring higher transmission rates and Better performance optoelectronic devices.Optoelectronic devices with higher transmission rates and better performance are being explored.The emergence of Surface Plasmon Polaritons?SPPs?has made it possible to develop next-generation photonic integrated circuits?PICs?.Based on surface plasmon polaritons waveguide technology,a variety of Metal-Insulator-Metal?MIM?structures of optoelectronic devices have been successfully designed,such as filters,sensors,beam splitters,etc.In this thesis,two novel filters are proposed based on the MIM surface plasmon waveguide structure,which are the convex ring MIM structure filter constructed by the boundary coupling method and the oblique symmetric double L-shaped MIM structure filter constructed by the aperture coupling method.The finite element method?FEM?is used to numerically simulate the proposed filters to obtain the magnetic field distribution map,transmission line and resonant wavelength distribution.For the proposed convex ring structure filter,it has the characteristics of narrow transmission peak and smooth spectral line,and the stop-band transmittance is as low as 0.001,and the pass-band transmittance is up to 0.977.When the structural parameter h₂ and effective refractive index of the medium n_eff are increased,the corresponding transmission spectrum will be significantly red-shift.When the structural parameter L₁is increased,the transmission spectrum has almost no change.The structural parameters are adjusted and optimized,and the corresponding resonant wavelengths can be distributed in the vicinity of the first optical communication window?850 nm?and the third optical communication window?1550 nm?,which can be well applied to the three windows of optical communication as wavelength selection filter.For the proposed obliquely symmetric double L-shaped filter,the red shift or blue shift phenomenon can also occur by adjusting the transmission parameters of the structural parameters.The pass-band's transmission can reach 0.964 which near the first communication window,the stop-band's transmission can as low as 0 which near the second communication window and the third.Besides,its pass-band and stop-band all have a wide bandwidth,which can be used as a bandpass/bandstop hybrid filter.In addition,based on the proposed two structures,two corresponding improved structures are proposed.The filters designed in this thesis have certain application prospect in fiber-optic communication and wavelength division multiplexing systems.