关键词: 亚波长光栅, 共振吸收谱, 近场特性, 空心光场

Abstract:

In this paper, the spectral characteristics and the near field intensity distribution of the visible band of the subwavelength metallic grating are studied, Influence of structural parameters on the spectrum and intensity distribution are studied by using the COMSOL multi physical field coupling method. It is found that the subwavelength metallic grating has the resonance absorption spectrum, at the peak of absorption rate, it exhibits a standing wave pattern of surface plasmons. By choosing appropriate structure parameters, a dark hollow mode is obtained, and it can be used to realize atomic trapping and guiding based on the subwavelength grating. Our result has a certain reference significance for the theory research and the application of the subwavelength grating.

Key words: subwavelength grating, the resonance absorption spectrum, the near field characteristics, dark hollow mode