Research And Application Of Extraordinary Optical Transmission In Subwavelength Metal Microstructure

As the development of technology,devices start being more and more small.When the device reaches a very small size,however,the electronic device faces a limit.On the other hand,optical signals are transmitted in optical fibers,but most of the devices what we using are still electronic devices.This involves a process that requires the conversion from optical signals to electrical signals.Our current photoelectric conversion efficiency is relatively low,and there is no good way to further increase the transmission rate,or the cost is relatively high.The discovery of extraordinary optical transmission offers new possibilities for making optical devices.Subwavelength metal microstructures can break through the limits of the miniaturization of electronic devices,while optical devices no longer consider the issue of photoelectric conversion efficiency.Based on the extraordinary optical transmission phenomenon,this paper analyzes the physical mechanism of the extraordinary optical transmission by using the simplified model of the micro hole array--two-dimensional slit groove structure.It mainly consists of two parts:Based on the research at home and abroad,the physical mechanism of extraordinary optical transmission phenomenon of symmetrical double-groove structure was studied.Through rigorous theoretical derivation,a good theoretical model is obtained that agrees well with the numerical solution.The results show that the transmissivity of the symmetric double-groove structure exhibits a certain periodicity with the change of the distance between the slits of the groove,and a double peak appears.The main cause of this phenomenon is that:unlike the structure of a single groove,the two grooves have interact with each other.In order to further verify the effect of cavity mode resonance on the transmission characteristics of the slits and grooves,we systematically studied the relationship between groove geometric parameters and transmittance by adding rectangular grooves in the slits.And we give a qualitative theoretical explanation.The variations of the groove parameters influence the excitation of surface plasmons and the interaction of surface plasmons with incident light.The final transmission enhancement and weaken are determined by surface plasmon and cavity mode resonance together.The results of this paper have certain guiding significance for us to further understand the physical mechanism of extraordinary optical transmission phenomena.It also provides theoretical basis for the application of extraordinary optical transmission in practical engineering.