Liu Xin, Chen Shuqi, Zang Weiping, Tian Jianguo
School of Physics, Nankai University, Tianjin, China.
Opt Express. 2011 Apr 25;19(9):8233-41. doi: 10.1364/OE.19.008233.
A triple-layer guided-mode resonance Brewster filter consisting of a homogeneous layer and two identical gratings with their refractive indices equal to that of the homogeneous layer is presented. The spectral properties of this filter are analyzed based on the coupling modulation of two identical binary gratings at Brewster angle for a TM-polarized wave. The grating layer between substrate and homogeneous layers can significantly change the linewidth and resonant mode position, which are due to the asymmetric field distribution inside the grating layers. The tunability of the resonance can be altered on different resonant channels and a practical filter can be obtained in TM2 waveguide mode. Variation of filling factor can alter the field localization in the grating structure and significantly adjust the linewidth of the filter.
提出了一种由均匀层和两个折射率与均匀层折射率相等的相同光栅组成的三层导模共振布儒斯特滤波器。基于两个相同二元光栅在布儒斯特角对TM偏振波的耦合调制，分析了该滤波器的光谱特性。衬底和均匀层之间的光栅层可显著改变线宽和共振模位置，这是由于光栅层内部场分布不对称所致。共振的可调性可在不同的共振通道上改变，并且在TM2波导模式下可获得实用的滤波器。填充因子的变化可改变光栅结构中的场局域化，并显著调整滤波器的线宽。
