Li Kebin, Clime Liviu, Tay Lilin, Cui Bo, Geissler Matthias, Veres Teodor
Industrial Materials Institute, National Research Council Canada, 75 de Mortagne, Boucherville, Québec, J4B 6Y4, Canada.
Anal Chem. 2008 Jul 1;80(13):4945-50. doi: 10.1021/ac800149d. Epub 2008 May 29.
Arrays of Au nanowells (NWs) were fabricated by electron-beam lithography (EBL) and characterized by surface plasmon resonance (SPR) and surface-enhanced Raman scattering (SERS). It is revealed that these Au NW arrays exhibit multiple SP resonances that can be tuned by adjusting the geometrical characteristics of the NWs. SERS activity of Au NWs was confirmed for a range of excitation wavelengths and a number of model compounds including rhodamine 6G (R6G), phthalazine, and single-stranded oligonucleotides. According to numerical simulations based on the discrete dipole approximation (DDA), SERS enhancement originates from high electromagnetic fields (hot spots) localized both inside and outside individual NWs. In addition, far-field intercoupling effects between NWs have been observed experimentally in arrays with subwavelength pitch sizes. We show that the SERS enhancement factors can also be tuned and optimized by adjusting the geometry of NWs.
通过电子束光刻（EBL）制备了金纳米孔阵列（NWs），并通过表面等离子体共振（SPR）和表面增强拉曼散射（SERS）对其进行了表征。结果表明，这些金纳米线阵列表现出多个表面等离子体共振，可通过调整纳米线的几何特征来进行调节。对于一系列激发波长以及多种模型化合物，包括罗丹明6G（R6G）、酞嗪和单链寡核苷酸，均证实了金纳米线的SERS活性。根据基于离散偶极近似（DDA）的数值模拟，SERS增强源于单个纳米线内部和外部的高电磁场（热点）。此外，在具有亚波长间距尺寸的阵列中，通过实验观察到了纳米线之间的远场相互耦合效应。我们表明，通过调整纳米线的几何形状，也可以调节和优化SERS增强因子。
