级联型波导中古斯-汉欣位移的增强

Enhancement of Goos-Hnchen Shift with Cascade Optical Waveguides

前期的工作已经证明,由于共振效应和渗透深度的增加,利用毫米尺度对称金属包覆波导和自由空间耦合技术,可获得毫米量级的古斯-汉欣(Goos-Hnchen)位移。本文在此基础上,利用一对对称金属包覆波导组成级联型结构,研究了这种结构中古斯-汉欣位移的增强效应。实验结果表明:当激光波长变化43pm时,由CCD探测器测量得到的古斯-汉欣位移达到了2215m,约为单级波导古斯-汉欣位移的2倍,实验结果与理论推导完全一致。

According to the previous study,we have proved that,by using the symmetrical metal-cladding optical waveguide with millimeter scale and the free-space coupling technique,one millimeter order of Goos-Hnchen shift can be obtained due to the resonance effects and the increase of the penetration depth.On the basis of this,enhancement of Goos-Hnchen shift is demonstrated with a pair of symmetrical metal-cladding optical waveguides in a cascaded structure.It is experimentally shown that the Goos-Hnchen shift measured from a CCD detector is 2215 μm with a change of 43 pm in the light wavelength,which is just two times of that exhibited from a single waveguide.Experimental result agrees well with the theoretical prediction.This method shows potential application prospect in optical switching and filtering.