Kim Hyun Chul, Cheng Xing
Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 77843-3128, USA.
Opt Express. 2009 Sep 28;17(20):17234-41. doi: 10.1364/OE.17.017234.
We numerically investigate the optical field enhancement supported by gap surface plasmon polaritons (GSPPs). The optical field enhancement at the edge of the nanostructures originates not only from localized surface plasmon (LSP) resonance but also from multiple scattering and coupling of GSPPs in the spacer region between two metal plates. By calculating field enhancement, we predict surface-enhanced Raman scattering (SERS) enhancement factors (EFs) of up to 10(11) for equilateral triangular nanostructures. The SERS EFs as a function of the geometry and dimension of the nanostructures are obtained by simulation. The effect of the surrounding medium on the SERS EFs is also investigated. Coupled with easy fabrication, those nanostructures are expected to find important applications in optical sensing as a SERS-active substrate.
我们对间隙表面等离激元极化激元（GSPPs）所支持的光场增强进行了数值研究。纳米结构边缘处的光场增强不仅源于局域表面等离激元（LSP）共振，还源于两个金属板之间间隔区域中GSPPs的多次散射和耦合。通过计算场增强，我们预测等边三角形纳米结构的表面增强拉曼散射（SERS）增强因子（EFs）高达10(11)。通过模拟获得了作为纳米结构几何形状和尺寸函数的SERS EFs。还研究了周围介质对SERS EFs的影响。结合易于制造的特点，预计这些纳米结构作为SERS活性基底在光学传感中会有重要应用。
