Author Affiliations
Abstract
1 Institute of Photonics, Faculty of Science, Ningbo University, Ningbo 315211, China
2 Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
3 Department of Electrical and Computer Engineering, Dalhousie University, Halifax, NS B3J 2X4, Canada
The optical properties of a three-arm plasmonic nanoantenna with and without broken symmetry were analyzed in detail. For the symmetrical structure, the local electric field can be significantly enhanced and well confined within the feed gap, whilst the extinction spectrum illustrates polarization independence. With broken symmetry, multi-wavelength resonances are observed due to the single dipole resonance and dipole–dipole coupling effect, and wide tunability is also available through minor structural adjustment. Especially when illuminated by a circularly polarized light beam, the extinction and the electric field distribution can be effectively modulated by just varying the incident wavelength.
260.5430 Polarization 290.2200 Extinction Chinese Optics Letters
2018, 16(5): 052501
1 宁波大学 理学院，浙江 宁波 315211
2 南通大学 理学院，江苏 南通 226007
3 长春理工大学 光电子工程学院， 长春 130022
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.
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 光子学报
2016, 45(10): 1024001
