基于anapole模式高灵敏度检测的等离子体结构设计  

Plasmonic Structure Design for High-Sensitivity Detection Based on anapole Mode

作　　者：李智慧 王艳红[1] 武京治[1] Li Zhihui;Wang Yanhong;Wu Jingzhi(School of Information and Communication Engineering,North University of China,Taiyuan,Shanxi 030051,China)

机构地区：[1]中北大学信息与通信工程学院,山西太原030051

出　　处：《激光与光电子学进展》2021年第3期113-117,共5页Laser & Optoelectronics Progress

摘　　要：设计一种基于anapole模式的高灵敏度传感器,由金属反射层、SiO 2薄膜和开槽硅圆盘构成。利用硅纳米阵列中的anapole模式激发金属反射层以产生等离子体共振,通过模式匹配和相邻结构之间的耦合可以在周期性纳米结构中产生尖锐的共振峰。采用时域有限差分法对结构进行仿真分析,研究不同参数对传感器灵敏度的影响。仿真结果表明,纳米结构可以显著增强局部电场,同时降低能量的吸收率。利用圆偏振光可以在纳米结构周围实现自旋-轨道角动量的转换,有利于对神经递质等生物分子的传感。A high sensitivity sensor based on anapole mode is designed,which consists of a metal reflector,a SiO 2 thin film and a slotted silicon disk.The anapole mode in silicon nanoarray is used to excite the metal reflector layer to generate plasma resonance,and sharp resonance peaks can be generated in the periodic nanostructures through mode matching and coupling between adjacent structures.The structure is simulated and analyzed by finite difference time domain method,and the influence of different parameters on the sensitivity of the sensor is studied.The simulation results show that the nanostructures can significantly enhance the local electric field and reduce the energy absorption rate.The spin-orbital angular momentum conversion around nanostructures can be realized by using circularly polarized light,which is beneficial to the sensing of biomolecules such as neurotransmitters.

关 键 词：衍射 anapole模式 等离子体 谐振波 高灵敏性 

分 类 号：O436[机械工程—光学工程]