Surface-enhanced monomolecular super-Raman scattering substrate based on Fano resonance type silver nano trimer

The invention provides a surface-enhanced monomolecular super-Raman scattering substrate based on a Fano resonance type silver nano trimer. The substrate is composed of three spindle-shaped nano trimer structure units with different lengths and widths. Two strong scattering peaks exist in a near-infrared region and a visible light region and correspond to the right shoulder peaks of first-order resonance and Fano resonance of a bright mode respectively, and near-field hot spots at two different frequencies occur at the same spatial position. By exciting different resonance modes, a significantly enhanced electric field can be obtained in near-infrared and visible light bands and the same space region, namely the gap position of the trimers, namely the near-field hot spots are generated atthe gap positions of the trimers (L1 =254 nm, D=50 nm, L2=90 nm and g=5 nm) and correspond to the super-Raman enhancement factors 1013-1014. 本发明提供了一种基于Fano共振型银纳米三聚体的表面增强单分子超拉曼散射基底，所述基底是由三个长度和宽度不同的纺锤形纳米三聚体结构单元组成。在近红外和可见光区域有两个强