Influence Of Dielectric Chirality On Extraordinary Optical Transmission

Since the phenomenon of extraordinary optical transmission was first discovered,it has been applied to many fields such as integrated optics,biosensing,and the manufacture of optoelectronic devices,which has attracted widespread attention.People have successively studied the influence of the shape of the metal nanopore structure,the dielectric environment,and the characteristics of incident light on EOT;in addition,there is currently an important trend to combine new materials,new structures,etc.with EOT.As an alternative material,the combination of chirality and EOT may produce some attractive phenomena.At present,some studies have been conducted on the EOT characteristics of metal nanopore structures with structural chirality,but there are few studies involving the combination of dielectric chirality and EOT.This thesis numerically simulates the extraordinary optical transmission effects of metal nanopore structures with different shapes in chiral environment,and studies the extraordinary optical transmission characteristics of metal nanopore structures with different shapes in ordinary medium condition and chiral environment.Here,the metal nanopore structures studied mainly include the more representative circular and elliptical nanopore,triangular nanopore,rectangular nanopore and rhombic nanopore structures.It is found that there is always one or more transmission peaks in a certain band of metal nanopores in under non-dielectric chiral conditions,and the shape of nanopores and the angle of incidence strongly affect its EOT characteristics.When dielectric chirality is introduced into metal nanopores,the transmittance of the metal nanopore structure will not only decrease,but its position will also change.In addition,the nanopore structure will also produce different responses to the two types of circularly polarized light,resulting in a difference in the transmittance of the two polarized lights,which can also be understood as circular dichroism.However,when dielectric chirality is introduced into the dielectric layer above the metal nanopore structure,it only has a certain effect on its transmittance.By comparing the difference of the EOT characteristics of the metal nanopore structure under the two conditions of non-dielectric chirality and dielectric chirality,we confirmed that changing the chirality of the environment can achieve the control of the size and position of the transmittance of the metal nanopore structure.