Matsuda Toyonori, Tsunoda Isao, Nagata Masanori, Kawakita Takao, Noguchi Shumpei
Appl Opt. 2022 Dec 1;61(34):10178-10187. doi: 10.1364/AO.474161.
We experimentally investigate the polarization property of the specularly reflected light from an anodic porous alumina (APA) membrane coated with a gold (Au) thin film. As a result, we reveal a rapid change in the normalized Stokes parameter of the specularly reflected light around the angle of incidence at which the resonance absorption of the incident light occurs. The rapid change in demonstrates that the specularly reflected light can rapidly be right- to left-elliptically polarized via linear polarization at the zero-crossing point of . Moreover, is located close to , and as well as depend on the occurrence conditions of the resonance absorption. From numerical aspects based on the Maxwell Garnett effective medium approximation, we clarify that the rapid change in accompanies the Fabry-Pérot (FP) resonance in the Au-coated APA membrane. The numerical results also suggest that the change in the refractive index of the filling material into nanopores of the Au-coated APA membrane can be successfully estimated by using the rapid change in .
我们通过实验研究了涂有金（Au）薄膜的阳极多孔氧化铝（APA）膜的镜面反射光的偏振特性。结果表明，在入射光发生共振吸收的入射角附近，镜面反射光的归一化斯托克斯参数 发生了快速变化。 的快速变化表明，镜面反射光可以在 的零交叉点通过线性偏振迅速从右旋椭圆偏振变为左旋椭圆偏振。此外， 靠近 ，并且 以及 都取决于共振吸收的发生条件。基于麦克斯韦-加尼特有效介质近似的数值分析，我们阐明了 的快速变化伴随着涂金APA膜中的法布里-珀罗（FP）共振。数值结果还表明，利用 的快速变化可以成功估算涂金APA膜纳米孔中填充材料的折射率变化。
