单一亚波长孔径增强透射效应的传输线模型

为了研究亚波长孔径的增强透射效应,把传输线理论引入到了单一亚波长金属孔径的增强光学透射效应中。把金属孔径看成传输线,将电流在传输线上的传输和类Fabry-Pérot腔联系起来;把孔径的出射面看成是传输线的输出端,将出射面的电流看成是一种局域的衰逝电流,电流经传输线在传输线的输出端以天线辐射的形式辐射电磁波。解释了孔径透射的近场分布问题、孔径增强透射峰的位置问题和透射峰位置随金属板厚度的红移问题,得到了与其它理论和实验一致的结果,对开发基于增强透射的亚波长元件具有重要的参考价值。

Transmission line model of enhanced transmission through a single subwavelength aperture

The transmission line model of enhanced optical transmission of a single subwavelength hole in a metal film is investigated. The metal aperture is regarded as a transmission line, and the transmission line performs as a Fabry-Pérot-like cavity, which channels the currents to the output plane. The currents transform as a localized decayed sources, and emission energies in form of antennas. The new model satisfies the near-filed distribution and the red-shift of the peak, which is determined by the condition of Fabry-Pérot resonance, as the increased depth of the metal film. The model is significant to develop subwavelength elements based on enhanced transmission.