The properties of periodic dielectric structures coated with a thick metal layer, which allow enhancing an inelastic light scattering signal by more than eight orders of magnitude at a laser pump wavelength of 1064 nm, have been studied. It has been shown that the giant resonance enhancement of the Raman signal in the near infrared range is ensured by additionally enhanced plasma resonance and by geometrical resonance between the sizes of the dielectric structure and the wavelength of laser radiation. The dependence of the enhancement factor of the Raman scattering on the height of columns in periodic dielectric structures, as well as the dependence of the enhancement factor on the thickness of the metallic coating, has been studied. New resonance modes have been revealed, for which the height of dielectric columns is 1/4, 1/2, and 3/4 of the wavelength of laser radiation. It has been shown that record high enhancement factors of the Raman scattering can be reached in the near infrared range, which is also due to a high Q factor of plasma waves in metals at these frequencies.

中文翻译：

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近红外光谱范围内拉曼散射巨增强的元结构。

已经研究了涂覆有厚金属层的周期性介电结构的特性，该特性可以在1064 nm的激光泵浦波长下将非弹性光散射信号增强八个数量级以上。已经表明，通过额外增强的等离子体共振以及介电结构的尺寸和激光辐射的波长之间的几何共振，可以确保在近红外范围内拉曼信号的巨大共振增强。研究了拉曼散射增强因子对周期性介电结构中柱高的依赖性，以及增强因子对金属涂层厚度的依赖性。揭示了新的共振模式，电介质柱的高度为1 / 4、1 / 2，和激光辐射波长的3/4。已经表明，在近红外范围内可以达到记录的拉曼散射增强因子，这也是由于在这些频率下金属中等离子体波的Q因子。