光子学报, 2015, 44 (6): 0624002, 网络出版: 2015-06-25
混合表面等离子体微盘腔模式特征及传感特性
Mode and Sensing Properties of Hybrid Plasmonic Microcavity
混合表面等离子体微腔 SPP-WG混合模式 品质因子 有效模式体积 高灵敏度传感 Hybrid plasmonic microcavity Hybrid plasmonic mode Quality factor Effective mode volume High sensitive sensor
摘要
为了实现高Q值极小模体积的表面等离子体微腔,提出一种混合表面等离子体微盘腔,介质微盘上放置横截面为矩形的金属纳米环形条,微盘腔中间由低折射率材料隔离.用有限元法对混合微腔的模式特性进行数值模拟,研究了其品质因子、有效模式体积和腔外能量比随器件几何尺寸的变化规律.结果表明,所设计微盘腔具有较低的传播损耗、较强的光场约束能力和较高的腔外能量比,品质因子高达7 000,最小模体积仅为0.315 μm3,可实现高灵敏度折射率传感.
Abstract
A hybrid plasmonic microcavity consisting of a silicon microdisk which is separated from a silver toroidal strip by a low-permittivity dielectric is proposed to achieve high quality factor as well as small mode volume.Mode properties such as quality factor,effective mode volume and energy ratio have been investigated by employing a finite element method and analyzed considering the different structure geometry.Simulation results reveal that this kind of hybrid microcavity maintains low propagation loss with high quality factor ~ 7000,high field limits with small mode volume 0.315 μm3,high energy ratio and can realize a refractive index sensor with high sensitivity.
张蒙, 吴根柱, 王聪, 刘彬斌, 陈达如. 混合表面等离子体微盘腔模式特征及传感特性[J]. 光子学报, 2015, 44(6): 0624002. ZHANG Meng, WU Gen-zhu, WANG Cong, LIU Bin-bin, CHEN Da-ru. Mode and Sensing Properties of Hybrid Plasmonic Microcavity[J]. ACTA PHOTONICA SINICA, 2015, 44(6): 0624002.