Study On Surface Plasmon Polaritons Invisibility Cloaking Devices Based On Infinitely Anisotropic Meta Mate Rial

Surface plasmon polaritons(SPPs)is an oscillating electromagnetic wave,generates at the interface of metal and medium.It can propagate along the horizontal direction of the interface,and its energy is confined to the surface of the metal but attenuates exponentially along the vertical direction of the interface.Depends on its specific characteristics,such as local distribution and breaking diffraction limit,SPPs is widely used in biosensing,integrated circuit etc.The applications of SPPs in optoelectronic devices have the potential to shrink the scale of optoelectronic device to nanoscale.However,when the translation invariance.is broken,stuch as a bump on the surface,or a sharp corner,may cause severe scattering of the SPPs.But the designers can not provide smooth route for SPPs' propagation in miniaturized device,which will decrease the transmission severely.So guiding the SPPs through the bump or corner with no loss has become an urgent problem to be solved in this field.In order to solve this problem,a method,using infinitely anisotropic metamaterial(IAM)to design SPPs invisibility cloaking devices,was proposed in this paper.This key problem may be solved by controlling the propagation path of SPPs with IAM.By utilizing the non diffraction characteristics of this medium,we analyzed the transmittance of this medium and the foll transmission formula was obtained.Based on this formula,three invisibility cloaking devices were designed.Then we validated these devices' performance in simulation.Considering the complexity of experiment in optical frequency,we utilized the spoof surface plasmon polaritons(Spoof SPPs)to do the experiment for two devices in microwave frequency.The results of simulation and experiment show that SPPs invisibility cloaking devices can effectively guide SPPs through bump with no loss.This method is simple and robust.The devices are able to work in a broad band.The method proposed in this paper will extend the applications of guiding SPPs and photonic circuits.