Surface-enhanced resonance Raman scattering and background light emission coupled with plasmon of single Ag nanoaggregates
Surface-enhanced resonance Raman scattering and background light emission coupled with plasmon of single Ag nanoaggregates
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DOI：
10.1063/1.2177662
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发表时间：
2006-04-07
影响因子：
4.4
通讯作者：
Ozaki, Y
中科院分区：
文献类型：
--
作者：
Itoh, T;Biju, V;Ozaki, Y
我们研究了孤立的单一聚集体的银纳米粒子（银纳米聚集体）上吸附的罗丹明6G分子的光学性质，实验揭示等离子体共振瑞利散射，表面增强共振拉曼散射（SERRS），其背景光发射之间的相关性。从背景发射最大值的激发激光能量依赖性的缺乏，我们得出结论，背景发射是发光，而不是拉曼散射。SERRS和背景发射的偏振依赖性是相同的最低能量的等离子体共振最大值，这是与纵向等离子体激元。从共同的偏振依赖性，我们确定，最低能量的等离子体与SERRS和背景发射耦合。此外，我们发现，具有较高的品质因子（Q因子）的最低能量的等离子体激元产生较大的SERRS和背景发射强度。此外，我们确定的Q因子的SERRS强度的依赖性是类似的背景发射强度。这种相似性直接支持我们证明通过与共同的等离子体激元辐射模式耦合来增强SERRS和背景发射。(c)2006年，美国物理学会。
We investigated the optical properties of isolated single aggregates of Ag nanoparticles (Ag nanoaggregates) on which rhodamine 6G molecules were adsorbed to reveal experimentally a correlation among plasmon resonance Rayleigh scattering, surface-enhanced resonance Raman scattering (SERRS), and its background light emission. From the lack of excitation-laser energy dependence of background emission maxima we concluded that the background emission is luminescence, not Raman scattering. The polarization dependence of both SERRS and background emission was the same as that of the lowest-energy plasmon resonance maxima, which is associated with a longitudinal plasmon. From the common polarization dependence, we identified that the lowest-energy plasmon is coupled with both SERRS and background emission. In addition, we revealed that the lowest-energy plasmon with a higher quality factor (Q factor) yields larger SERRS and background emission intensity. Also, we identified that the Q factor dependence of the SERRS intensity was similar to that of the background emission intensity. This similarity directly supported us to demonstrate an enhancement of both SERRS and background emission by coupling with a common plasmon radiative mode. (c) 2006 American Institute of Physics.