基于局域和传播型表面等离激元长程耦合的新型表面/针尖增强拉曼光谱和传感基底

项目名称： 基于局域和传播型表面等离激元长程耦合的新型表面/针尖增强拉曼光谱和传感基底

项目编号： No.21503181

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 王翔

作者单位： 厦门大学

项目金额： 21万元

中文摘要： 基于金属纳米结构的表面等离激元由于能将光局域在表面纳米级的范围内，并得到强的电场增强，因此受到越来越多的关注。而如何将具有高增强的局域表面等离激元（LSP）与低损耗，对表面折射率改变高敏感的传播型表面等离激元（PSP）有效耦合，同时发挥两者的优势成为其应用的关键。本项目拟通过电磁场理论模拟，采用激发光路和收集光路分离的方法，系统研究能够低成本大批量制备的金属粒子与金属膜、针尖与金属膜以及周期阵列与金属膜中LSP和PSP耦合的光学模式和效率，提出远距离的多个金属纳米粒子LSP通过驻波场的PSP实现长程和群体耦合的物理模型。进一步发展基于金属膜PSP的纯粹近场激发的表面增强拉曼和针尖增强拉曼光谱基底。通过全息光刻引入周期结构，丰富金属纳米结构LSP和PSP耦合的光学模式并大大提高表面光学性质的可调性，从而实现同时利用LSP的近场增强提供指纹信息和窄带PSP的高灵敏度折射率传感的新型检测基底。

中文关键词： 局域表面等离激元；传播型表面等离激元；表面增强拉曼光谱；针尖增强拉曼光谱；传感器

英文摘要： The surface plasmon based on metal nanostructures has attracted plenty of attention due to its capability of confining lights in nanoscale and providing enhanced electric field. The key issue in applying surface plasmon is how to effectively combine the advantages of localized surface plasmon (LSP) with strongly enhanced electric field and propagated surface plasmon (PSP) with low loss and ultrahigh sensitivity to the change of surface refractive index. In this project, we try to systematically investigate the coupling of LSP and PSP of nanoparticle-metal film, tip-metal film and periodical array-metal film systems，which can be conveniently fabricated with low cost, with electromagnetic field simulation and experiments with separating excitation and collection paths. We aim to propose the physical model to understand the long-range and collective coupling of LSP of multiple metal nanoparticles through PSP that is a standing wave. Then we will develop new substrates for surface and tip enhanced Raman spectroscopy with purely near-field excitation from PSP based on the understanding. Furthermore, periodical structure will be fabricated on the metal film with holographic method to increase the modes of coupling LSP and PSP and improve the flexibility of optical properties of the surface. Then we expect to realize a new type of sensor that is able to simultaneously provide fingerprint information based on the near-field enhancement of LSP and ultrahigh sensitivity of refractive index change based on the narrow band of PSP.

英文关键词： Localized surface plasmon;Propagated surface plasmon;Surface enhanced Raman spectroscopy;Tip enhanced Raman spectroscopy;Sensor