Nanoapertures in a metallic film exhibit extraordinary optical transmission (EOT) owing to the surface plasmon resonance. Their transmission properties are known to be dependent on the structural parameters of the nanoapertures. In addition, the polarization of light has also a crucial influence on the transmission spectrum. In this study, we numerically found that the polarization state is a sensitive parameter in plasmonic EOT only when the gap size between triangular nanoapertures is less than ~ 20 nm. For a polarization of the light perpendicular to the axis between the nanoapertures, the optical transmission spectrum is nonlinearly redshifted with decreasing gap size. This spectral shifting of the transmission has potential applications for active optical filters, which can be manipulated by the polarization of light or by adjusting the gap size.

中文翻译：

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偏振相关的表面等离激元耦合在非凡光学传输中的光谱移位

由于表面等离子体共振，金属膜中的纳米孔表现出非凡的光学透射（EOT）。已知它们的透射性质取决于纳米孔的结构参数。另外，光的偏振对透射光谱也具有至关重要的影响。在这项研究中，我们从数字上发现，只有当三角形纳米孔之间的间隙尺寸小于〜20 nm时，极化状态才是等离子EOT中的敏感参数。对于垂直于纳米孔之间的轴的光的偏振，光透射光谱随着间隙尺寸的减小而非线性地红移。传输的这种光谱偏移对于有源光学滤波器具有潜在的应用，