法诺光栅的共振特性研究

针对亚波长光栅的共振特性,设计了一种基于法诺共振的亚波长光栅并研究了其共振特性。利用光学模拟软件FDTD Solutions对该光栅结构进行数值模拟,在可见光波段,对影响光栅性能的周期、折射率、占空比等光栅参数进行了研究,从而得到了一种共振强度高、谱线精细、共振峰位置可控的法诺共振谱线。该研究成果可用来研制1 nm精度的光谱滤波器。

Study on resonance characteristics of Fano grating

The study of the resonance characteristics of sub-wavelength gratings has always been one of the most important part of optics. In this paper, a sub-wavelength one-dimensional grating design based on Fano resonance is proposed. Compared with the guided-mode resonance, the Fano resonance has stronger near-field enhancement, finer spectrum and higher sensing quality factor. The optical simulation software, FDTD Solutions, is used to simulate the structure of the grating. The parameters affecting the diffraction performance of the grating are studied in detail, including the period, refractive index and duty ratio of the grating. The simulation results show that Fano resonance lines have high resonance intensities, fine spectral lines and controllable resonance positions in the visible light region. Based on this discovery, the one-dimensional grating structures proposed in this work could be utilized as a wavelength selector with an accuracy of less than 1 nm.