标题： 金属薄膜中不对称填充的狭缝，根据光的波长将光束分成两部分 显示英文标题

标题： Asymmetrically filled slits in a metal film that split a light beam into two depending on its wavelength

摘要： 通过应用散射波理论，可以以解析方式研究任意排列的多个狭缝在金属薄膜上穿孔并填充不同狭缝介质材料的电磁响应。 在这里，通过金属薄膜中不对称填充的狭缝对光束进行波长依赖的分裂，全面探讨了利用狭缝内和狭缝间双波干涉的现象。 我们考虑一个在金膜上穿孔的三狭缝结构，其中中间的狭缝通过窄高斯光束用于表面等离子体激元的激发，而两侧的狭缝则用于检测从中间不透明狭缝传播过来的透射表面等离子体波，分别在特定波长或两倍于该波长下进行检测。 对于这种提出的简单结构，我们表明，在特定波长下，两个侧向观察狭缝中只有一个可以处于通过状态，但当波长为该波长的两倍时，另一个被阻挡的狭缝将变为通过状态，这需要在深亚波长区域对狭缝深度、狭缝介质和狭缝间距进行特定设计。 在这种意义上，我们的模型中表面等离子体介导的光传输变得对波长敏感，单个光束可以在平行于阵列的横向方向根据其波长被分离成两个。 这为我们提供了一种独特的非光谱方法，在近场区域直接进行光学读取的方式。 显示英文摘要

摘要： By applying a scattering-wave theory, the electromagnetic response of an arbitrary array of multiple slits perforated on a metallic film and filled with different slit dielectric materials can be studied in an analytical way. Here, the wavelength-dependent splitting of a light beam into two by asymmetrically filled slits in a metal film using intra- and inter-slit dual-wave interferences is fully explored. We consider a triple-slit structure perforated on a gold film, where the middle slit is used for the surface-plasmon excitation by a narrow Gaussian beam while the two side slits are used for the detection of a transmitted surface-plasmon wave propagated from the middle opaque slit either at a particular wavelength or at double that wavelength, respectively. For this proposed simple structure, we show that only one of the two side observation slits can be in a passing state for a particular wavelength, but the other blocked slit will change to a passing state at double that wavelength with a specific design for the slit depth, slit dielectric, and inter-slit distance in the deep sub-wavelength regime. In this sense, surface-plasmon mediated light transmission becomes wavelength sensitive in our model, and a single light beam can be separated into two according to its wavelength in the transverse direction parallel to the array. This provides us with a unique way for direct optical reading in the near-field region using a non-spectroscopic approach.