Study Of SPP In Nanostructure

This paper studies the propagation characters of SPPs in nanostructure using FDTD simulation software. There are six chapters:In chapter 1, the basic concepts, research significance and the situation of plasmonics and waveguide are introduced.In chapter 2, we introduce the basic knowledge of Finite Difference Time Domain (FDTD). First of all, Yee cell and Maxwell Equations are introduced to describe the theory of FDTD method. Further more, calculation accuracy and stability are discussed. At last, absorbing boundary conditions are given.In chapter 3, we study the nanostripe waveguide. An asymmetric structure is simulated. It is observed that the Surface Plasmon Wave propagates not only with the attenuation but also with oscillations. Explanations of the above phenomenon are given that the oscillation is caused by coupling of SPPs in the metal-air interface and dielectric-metal interface.In chapter 4, we study two types of waveguides. In the former part, the related factors of coupled localized surface plasmons in a metal nanosphere array are studied. In the latter part, three methods are used to simulate the beam splitter. The chapter sums up with comparisons between these methods:beam splitter with small angle between the two branches can be achieved by coupling of dielectric nanowires; When not concerning about the loss, beam splitter can be achieved by SPPs in silver waveguide; Using photonic crystal waveguide, we can get low-loss, large-angle beam splitter.In chapter 5, after a series of analysis in pure cylinder, we try to study the mode area in hybrid waveguide and analyze some factors related to it. This chapter ends up with theoretical analysis of some common modes.In chapter 6, the prospects of our work are discussed.