中国激光, 2016, 43 (11): 1113001, 网络出版: 2016-11-10
基于非对称单缝结构的表面等离子体定向激发
Directional Excitation of Surface Plasmons Based on Asymmetric Single-slit Structure
表面光学 表面等离子体 定向激发 角度调制 有限元分析法 optics at surfaces surface plasmons directional excitation angle modulation finite element method
摘要
表面等离子体的定向激发在光通信、生物传感、集成电路、纳米刻蚀等领域具有重要应用。提出了一种L型非对称单缝的表面等离子体定向激发结构。无须改变缝隙的结构参数,通过调节入射光的入射角度即可实现表面等离子体的单向和双向激发,起到全光开关调制的作用。详细阐述了L型缝隙的加工制作流程,利用COMSOL Multiphysics仿真软件对缝隙结构进行模拟仿真。仿真结果表明,非对称单缝结构可实现消光比在-16 dB~15 dB范围内连续可调的表面等离子体定向激发。该结构体积小,便于操控,易于加工,对微纳等离子体光学器件的研究具有指导意义。
Abstract
The directional excitation of surface plasmons play an important role in optical communication, biosensing, integrated circuit and nanolithography, etc. An asymmetric L-type single-slit structure which can excite surface plasmons directionally is proposed. Without changing structural parameters of the slit, both the unidirectional and the bidirectional excitations of surface plasmons can be realized by changing the incidence angle. The structure can also play a role in all-optical switch modulation. The machining process of the L-type single-slit is elaborated in detail. The slit structure is simulated by the COMSOL Multiphysics software. The results show that the asymmetric single-slit structure can realize the directional excitation of surface plasmons with a continuously adjustable extinction ratio from -16 dB to 15 dB. This single-slit structure occupies small area and is convenient for manipulation and machining, and it has guiding significance for the research on micro-nano plasmon optical devices.
胡玄, 刘会刚, 刘波. 基于非对称单缝结构的表面等离子体定向激发[J]. 中国激光, 2016, 43(11): 1113001. Hu Xuan, Liu Huigang, Liu Bo. Directional Excitation of Surface Plasmons Based on Asymmetric Single-slit Structure[J]. Chinese Journal of Lasers, 2016, 43(11): 1113001.