Superscattering Characteristics Of Subwavelength Cylindrical Artifical Structures

Scattering of light is ubiquitous in nature.When light interacts with an object,the electrons inside the object absorb energy and form oscillating dipole moments.These oscillating dipole moments re-emit light in different directions,which is called scattering.Light scattering enhancement and modulation of subwavelength objects are of great significance for fundamental research and potential applications in optical physics.Based on the subwavelength cylindrical artificial structure,this paper breaks through the single-channel limit and studies its supererscattering characteristics.It mainly includes the following contents:1.The superscattering characteristics of double layer graphene cylindrical system is studied.The traditional Mie scattering theory and transfer matrix method are employed to obtain the exact solutions for the discrete multimode resonances.We then seek the explicit conditions of resonantly overlapping different eigenmode resonances by scanning external tunable parameters,i.e.the chemical potential of graphene or the thickness of the double layer structure,and then we achieved superscattering.The performance of multifrequency superscattering effect is further validated from the scattering spectra,near-field and far-field distributions.Finally,we also analyze the relationship between the generation of superscattering points and the thickness of the cylindrical structure,the chemical potential of graphene and the dielectric constant of the core material.2.The superscattering characteristics of cylindrical structure composed of graphene and h BN materials are studied.The Boron nitride material has hyperbolic properties within its two Reststrahlen(RS)bands.Combined with this fact,we calculate and analyze the hybrid plasmonphonon multimode resonance based a subwavelength graphene/hexagonal boron nitride cylindrical system.It is found that the hybrid hyperbolic plasmon-phonon modes in this proposed rod structure can be finely manipulated to obtain the coincidence at multiple frequencies by tuning the chemical potential of graphene via some external parameters.As a consequence,we here attain the goal of a multifrequency superscatterer with high tunability.The performance of multifrequency superscattering effect is further validated from the scattering spectra,nearfield and far-field distributions.In addition,the tolerance of multifrequency superscattering and the enhancement of the scattering to structure vibrations,realistic material loss and the chemial potential of grapenene is also investigated in the numerical calculations.This paper provide a flexible and controllable platform in practical implementation to realize multifrequency superscattering of subwavelength cylindrical artifical structures,and efficiently tune the interation of the light and matter at the subwavelength scale.We remark that such a method can be applied to other subwavelength artificial structure systems and seek the possibility of efficient superscattering or superabsorption effects.