Research On Strong Cavity Interaction And Preparation Of Metal Nanoparticles Based On Surface Plasmon Polaritons

In recent years,researchers have paid more attention to surface plasmon polaritons in various fields such as physics,chemistry,biology and materials.Surface plasmons has achieved structured characterization of metals on the nanoscale,which in turn allows us to manipulate the properties of surface plasmon polaritons to explore new fields in basic science.As an important branch in the field of surface plasmons,strong coupling becomes more and more relevant to high-end emerging applications.Therefore,utilizing the properties of surface plasmon polaritons to design high intensity coupling systems has become a hot topic in academic research.Based on the content about surface plasmons,this paper will discuss different strong coupling systems.The main research content is as follows:In the strong exciton-plasmon coupling system,we have explored deeply about the preparation of the plasmon system.According to the types of excitons and the properties of metal nanostructures,gold nanorods were selected as the starting point for research.The entire experimental process has applied chemical methods,assisted by physical deposition,filtration and other methods.Finally,the forming metal nanoparticles exhibit good appearance and average size under the transmission electron microscope.By adjusting the chemical reagent dosage,gold nanorods with different aspect ratios can be synthesized successfully.Besides,the long-axis resonance wavelength of the sample can be continuously adjusted within a certain range.On this basis of gold nanorods,the preparation method of silver-coated gold nanorods(Au@Ag nanorods)has been studied.By wrapping the silver shell around the gold nanorods,silver-coated gold nanorod particles with sharp corners were finally synthesized.Due to the tip effect,these particles have wide application prospects in the strong exciton-plasmon coupling system.In the strong interaction system of the plasmon cavity,a metal-insulator-metal(MIM)system is designed,which has high application value in the field of sensing.In the entire MIM structure,we can increase the number of optical modes by adding cavities with different shapes.Through the interaction between the different modes,the significant coupling phenomena can be observed,which is characterized by high coupling strength.By changing the size of cavities,the position of resonance peak in transmission spectrum can be adjusted within a certain range,thereby realizing the regulation of the strong coupling system.In addition,we can adjust the position of the splitting valley in transmission spectrum by changing the background refractive index in the optical cavity.The system has a high sensitivity to refractive index,which indicates that this structure has potential application value in the sensing field.