一维等离激元晶格中的能带结构调控

由于具有将电磁波聚集到深亚波长体积的能力,表面等离激元在纳米光子技术研究工作中得到了广泛的应用.根据其性质,表面等离激元基本可以分为两大类:沿金属与介质界面传播的表面等离极化激元(SPPs)和束缚在金属表面的局域表面等离激元(LSPRs).SPPs和对应的自由空间电磁波之间存在明显的动量失配,光栅,即一维等离激元晶格,...

Energy Band Structure Control in One Dimensional Plasmonic Lattice

Due to its ability to concentrate electromagnetic waves into deep sub-wavelength volume, surface plasmons have been widely used in nanophotonics. Generally, surface plasmons can be divided into two categories: surface plasmon polaritons (SPPs) propagating along the interface between metal and medium, and localized surface plasmon resonance (LSPRs) bound to metal surface. There is an obvious momentum mismatch between SPPs and the corresponding free space electromagnetic wave. Grating, i.e. one-dimensional plasmonic lattice, is often used to compensate for this momentum mismatch and launch SPPs from free space. LSPRs refer to the surface plasmon localized around a single nanostructure under external light field excitation. When LSPRs are launched, the near-field enhancement effect can greatly increase the absorption and scattering of the incident light. In fact, one dimensional plasmon lattice supports both SPPs and LSPRs, which is an excellent foundamental structure for studying surface plasmon and its optical properties. Due to the coexistence of LSPR, there are much richer energy band structures in plasmonic lattice than in photonic crystals. In this review, we focus on one-dimensional plasmon lattice, and discuss the novel properties of metal plasmon from four aspects: band control, surface lattice resonance, bound states in continuum and Bose-Einstein condensation. These properties are of great significance to further promote the application of surface plasmon.