Investigation of plasmon properties of silver microsphere array demonstrated experimentally by tip-enhanced Raman spectroscopy
Investigation of plasmon properties of silver microsphere array demonstrated experimentally by tip-enhanced Raman spectroscopy
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通过尖端增强拉曼光谱实验证明银微球阵列的等离子体特性的研究
DOI：
10.1016/j.apsusc.2017.09.227
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发表时间：
2018
影响因子：
6.7
通讯作者：
Fang Yan
中科院分区：
文献类型：
--
作者：
Liu Yanqi;Zhao Lijiang;Li Xinjuan;Zeng Zhuo;Wang Peijie;Zhang Lisheng;Fang Yan
由于针尖增强拉曼光谱（TERS）具有高的空间分辨率和极高的探测灵敏度，因而受到越来越多的关注。然而，尖端的尺寸和形状，以及尖端衬底的距离有很大的影响TERS增强性能。本文采用真空热蒸发法在聚苯乙烯微球阵列上制备了银微球阵列。研究了罗丹明6 G（Rh 6 G）在银微球阵列上的二维表面增强拉曼散射（Sers）特性与入射光偏振方向的关系。在TERS中还揭示了针尖位置对银微球阵列表面等离子体分布的影响。此外，采用三维时域有限差分法（3D-FDTD）模拟了银微球阵列的表面电磁场分布。这些结果表明，“热点”在银微球阵列的表面上的分布具有依赖于入射激光的偏振方向。此外，随着尖端的引入，银微球阵列表面上的“热点”变得更加局部化并大大增强。这些结果对进一步研究表面等离子体共振生物传感具有一定的指导意义。
Due to high spatial resolution and extraordinarily high detection sensitivity of tip-enhanced Raman spectroscopy (TERS), it has attracted more and more attention. However, the tip size and shape, and tip substrate distance have a large impact on the TERS enhancement properties. In this study, a silver microsphere array was prepared on a Polystyrene (PS) microsphere array by vacuum thermal evaporation. And the correlation between the properties of two-dimensional surface-enhanced Raman scattering (SERS) mapping of rhodamine 6G (Rh6G) absorbed on the silver microsphere array and the polarization direction of the incident light was investigated. The effect of the location of the tip on the surface plasmon distribution of the silver microsphere array was also revealed in TERS. In addition, the surface electromagnetic field distribution of the silver microsphere array was simulated by three-dimensional finite-difference time domain (3D-FDTD) method. These results show that the distribution of ‘hot spots’ on the surface of the silver microsphere array has a dependency on the polarization direction of the incident laser. Moreover, with the introduction of the tip, the ‘hot spot’ on the surface of the silver microsphere array becomes much more localized and largely enhanced. These results obtained in this paper may have some significance for further studies on the surface plasmon resonance bio-sensing.