复合金属纳米盘二聚物的散射特性(英文)

Optical Scattering Properties of Bimetallic& Nanodisk Dimers

采用有限元方法(FEM)研究了一组相邻金纳米盘和银纳米盘的表面等离激元共振(LSPR)特性,并根据等离激元杂化理论的偶极-偶极近似对复合金属纳米盘二聚物的散射光谱进行分析。结果表明,金-银纳米盘的等离激元散射强度受到入射电磁场偏振方向以及金属纳米盘二聚物的结构参数(如纳米盘直径、厚度和纳米盘间间隙)变化的影响。而且,随着纳米盘直径的增加,纳米盘厚度以及盘间间隙减小,金-银纳米盘二聚物等离激元共振散射谱共振峰位置会发生相应的红移。研究结果对于纳米金属异质二聚物等离激元物系在生物传感和光敏探测器件等方面的应用有重要意义。

According to the dipole-dipole approximation of plasmon hybridization theory, the localized surface plasmon resonance （LSPR） spectra of a pair of closely spaced gold and silver nanodisks, i.e. the plasmonic scattering characteristics of the bimetallic nanodisk dimer, have been studied by using the finite element method （FEM）. The results show that, the plasmonic scattering intensities of the bimetallic nanodisk dirner are affected by the polarization of incident electromagnetic field and its structure parameters, such as the disk diameter, thickness and gap distance. Moreover, the LSPR spectra of the bimetallic nanodisk dimer have considerably red-shift as the increasing of diameters, the decreasing of thicknesses and gap distance. It is significant to apply the heterodimer plasmonic systems on biological sensors and photosensitive detectors.