Wang Junqiao, Zhang Jia, Tian Yongzhi, Fan Chunzhen, Mu Kaijun, Chen Shu, Ding Pei, Liang Erjun
Opt Express. 2017 Jan 9;25(1):497-507. doi: 10.1364/OE.25.000497.
The development of new substrates for surface-enhanced spectroscopy is primarily motivated by the ability to design such substrates to provide the maximum signal enhancement. In this paper, we theoretically design and investigate a crisscross dimer array as a plasmonic substrate for enhancing coherent anti-Stokes Raman scattering (CARS). The plasmonic film-crisscross dimer array system can excite multiple resonances at optical frequencies. By properly designing structure parameters, three plasmon resonances with large field enhancements and same spatial hot spot regions can spectrally match with the pump, Stokes and anti-Stokes beams, respectively. The CARS signals are strongly enhanced by multi-resonance plasmon field enhancements. The estimated CARS factor can reach as high order as ~10 over conventional CARS without the plasmonic substrate.
用于表面增强光谱的新型基底的开发主要是受这样一种能力的驱动，即能够设计此类基底以提供最大的信号增强。在本文中，我们从理论上设计并研究了一种交叉二聚体阵列，作为用于增强相干反斯托克斯拉曼散射（CARS）的等离子体基底。等离子体薄膜 - 交叉二聚体阵列系统能够在光频下激发多个共振。通过合理设计结构参数，具有大场增强且空间热点区域相同的三个等离子体共振可以分别在光谱上与泵浦光、斯托克斯光和反斯托克斯光相匹配。CARS信号通过多共振等离子体场增强而得到强烈增强。估计的CARS因子相比于没有等离子体基底的传统CARS可高达约10的高阶。
