光子学报, 2016, 45 (10): 1024001, 网络出版: 2016-11-14
基于SPASER机制的偏心金壳纳米天线的多波长散射特性
Multi-wavelength Scattering Characteristics of a SPASER-based Off-centre Gold Shell Nanoantenna
表面等离激元受激辐射放大 局域表面等离子体共振 吸收截面 散射截面 纳米天线 SPASER Localized surface plasmon resonance Absorption cross-sections Scattering cross-sections Nanoantenna
摘要
基于表面等离激元受激辐射放大(SPASER)机制,提出了一种硅-金-硅三层核壳偏心纳米天线,并利用有限元法分析了其多波长散射特性.结果表明:在SPASER机制下,该纳米天线产生极大的散射光强度,且工作波长的数目随着硅核偏心率的增加而增加;当硅核的偏心率为9 nm 时,该纳米天线有4个共振峰,分别位于615 nm、 656 nm、724 nm 、847 nm,其对应的散射强度比非SPASER机制的纳米天线的散射强度高104倍;该纳米天线的散射波长还可以通过改变入射光的偏振角调节.基于SPASER机制的纳米天线对于设计多波长纳米激光器具有指导意义.
Abstract
Based on the mechanism of the Surface Plasmon Amplification by Stimulated Emission of Radiation (SPASER), an off-centre gold shell nanoantenna consisted of the silica-gold-silica three-layer core-shell was proposed and its multi-wavelength light scattering characteristics were numerically analyzed by using the Finite Element Method (FEM). For the SPASER-based nanoantenna, the results show that, the scattering wavelength number increases with the increasing of the silica core eccentricity and the scattering light intensity is greatly enhanced. When the eccentricity of silica core is 9 nm, the proposed nanoantenna has four intensity resonance peaks which are located at 615 nm, 656 nm, 724 nm and 847 nm respectively, and the corresponded scattering intensities are much higher than that of the non-SPASER one, about 104 times. Moreover, the scattering wavelengths of the proposed nanoantenna can be easily adjusted by changing the polarization angle of the incident light. The SPASER-based nanoantenna would be useful to design the multi-wavelength laser devices in nanoscale.
王勉, 张昊鹏, 许田, 周见红, 周骏. 基于SPASER机制的偏心金壳纳米天线的多波长散射特性[J]. 光子学报, 2016, 45(10): 1024001. WANG Mian, ZHANG Hao-peng, XU Tian, ZHOU Jian-hong, ZHOU Jun. Multi-wavelength Scattering Characteristics of a SPASER-based Off-centre Gold Shell Nanoantenna[J]. ACTA PHOTONICA SINICA, 2016, 45(10): 1024001.