Wang Yuyang, Zhang Tingting, Li Jinping, Wang Chi, Li Xuwei, Sun Meijuan, Fu Zhengkun, Zhang Zhenglong, Zheng Hairong
School of Physics and Information Technology, Shaanxi Normal University, Xi'an, PR China.
School of Physics and Information Technology, Shaanxi Normal University, Xi'an, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2020 Apr 15;231:118117. doi: 10.1016/j.saa.2020.118117. Epub 2020 Jan 25.
The development of new structures allows two-photon coherent anti-Stokes Raman scattering (TPCARS) to be strongly enhanced by multiple surface plasmon resonances (MSPRs). In this paper, plasmonic structure consisting of two Ag nanorods is designed and the enhancement of TPCARS is investigated. By properly selecting designing structure parameters, strong MSPRs peaks at 1020 nm and 505 nm are obtained, which can enhance the TPCARS signal based on the frequency match of the fundamental frequency and frequency doubling. The enhancement factor of TPCARS can reach as high as 3.66 × 10 with significant electric field enhancements under appropriate selection of system parameters. Furthermore, the two-photon process can be controlled at different optical frequencies by changing the geometric parameters of Ag nanorods. The new scheme advanced in this work can help to achieve single molecule level of CARS, and may have a potential to increase the intensity and resolution of nonlinear optical imaging.
新结构的发展使得双光子相干反斯托克斯拉曼散射（TPCARS）能够通过多表面等离子体共振（MSPR）得到显著增强。本文设计了由两个银纳米棒组成的等离子体结构，并研究了TPCARS的增强情况。通过适当选择设计结构参数，在1020纳米和505纳米处获得了强烈的MSPR峰，基于基频和倍频的频率匹配，这些峰可以增强TPCARS信号。在适当选择系统参数的情况下，TPCARS的增强因子可高达3.66×10，同时电场也有显著增强。此外，通过改变银纳米棒的几何参数，可以在不同的光学频率下控制双光子过程。这项工作中提出的新方案有助于实现单分子水平的相干反斯托克斯拉曼散射（CARS），并且可能有潜力提高非线性光学成像的强度和分辨率。
