The Research On Transmission Characteristics Of Spoof Magnetic Localized Surface Plasmon Waveguiding Over Arbitrary Bending Angles

The phenomenon of collective oscillation of tree electrons near the surface of the metal is called surface plasmons.Surface plasmons are a kind of surface wave and have great prospects of researches,which can't be emerged in the low frequency range.Then,researchers put forward the concept of spoof surface plasmons,which can generate electromagnetic wave by etching periodic grooves on the metal surface.Spoof magnetic localized surface plasmons,as one type of spoof surface plasmons,exist near metal particles,and can generate magnetic dipole mode.The magnetic dipole mode is azimuthally independent.Therefore,spoof magnetic localized surface plasmons(MLSPs)can transmit on a bent path.Furthermore,a wide variety of advanced plasmonic functional devices and highly integrated optical components could be developed from waveguides with large bending angles.Electromagnetic coupling and transmission characteristics of MLSPs based on the ultrathin metallic spiral structures(MSSs)are researched numeriacally and experimentally.The main content and research results are as follows:1.The resonant properties of the ultrathin MSS cell.The numerical simulaiton shows the MSS supports a magnetic resonance.By changing the turns of unit cell,horizontal and vertical magnetic field of MSS is affected.The maxium horizon magnetic magnititude of the magnetic mode with the number of turn 3 provides a confirmation for the following structure.2.The transmission properties of MSS pairs with different arrangements and with change of the rotation angle are studied to illustrate the coupling properties of the MSSs.When the rotation angle of different arrangements of the MSS pair changes,the simulated transmission frequency bands,resonant frequency and the distribution of field are roughly the same.Furthermore,the results of theoretical analysis,numerical simulations,and experiments of MSS pairs are in good agreement.Therefore,the spoof MLSPs can smoothly propagate even if the two MSSs are bent at a large angle.3.A long MSSs with rotating S-chain,translational M-chain and combined Y-chain are proposed to guide MLSPs propagating in bend path.Through the exact numerical simulations,the transmission frequency band ranges of the above structures are approximately same,and the fields distribution of these structures are almost identical.The experimental measurement of transmission of rotating S-chain is carried out to demonstrate that the MSSs bend chain can maintain the field amplitude in the corner.This implies that bent path has relatively little effects on the transmission efficiency and most MLSPs can transport through the bent path smoothly.4.Except for the studies of planar structure,researches of two-layer are carried out.First,the transmission of the single structural is studied,and then U-chain of two-layer is designed.The transmission bands of those two-layer structures are basically the same,and the two-layer structures can support longer-distance,large-angle spoof MLSPs.