金属表面等离激元耦合理论研究进展

Research progress of coupling theory of metal surface plasmon

金属表面等离激元作为一种微纳米结构中自由电子在光场作用下的集体振荡效应,由于其振荡电场被强烈地束缚在亚波长尺度范围内,可以作为未来微纳米光子回路及器件的信息载体,同时也可以在微纳米尺度上增强光与物质的相互作用.本文首先系统地从理论上总结金属与入射电磁波相互作用时的光学行为及性质,然后简述激发金属中不同等离激元模式的物理本质、金属表面等离激元振荡动力学过程及当前表面等离激元耦合理论的最新进展.

Metal surface plasmon is a collective oscillation effect of free electrons at the micro-nanostructure surface under the stimulation of incident light.Since the corresponding oscillating electric field is strongly bound below the sub-wavelength scale,it can be used as an information carrier for future micro-nano photonic circuit and device,and can also be used to enhance the interaction between light and matter on a micro-nano scale,such as surface enhanced photoluminescence,Raman scattering,nonlinear signal generation,surface enhanced catalysis,photothermal conversion,photovoltaic conversion,etc.How to theoretically understand the unique optical behavior dominated by the plasmon oscillation mode is one of the hot research spots in the field of surface plasmon photonics.In recent years,the theory of surface plasmon has been continuously improved with the support of a large number of experimental researches.In this paper,we first systematically summarize the optical behaviors and properties of metal under the excitation of incident electromagnetic waves,and then briefly describe the plasmonic modes existing in the metal and their corresponding physical natures,the oscillation dynamics process and the currently prevailing surface plasmon coupling theories.We hope that this paper can provide a theoretical basis for those researchers who have just dabbled in the field of surface plasmons and help them to master the relevant basic knowledge quickly.