有限微波波束在对称双三棱镜结构中的Goos-Hnchen与Imbert-Fedorov位移研究

Investigation on Goos-Hnchen and Imbert-Fedorov Shifts of the Bounded Microwave Beam in a Double-Prism Symmetry Structure

通过实验测量确立了对称双三棱镜结构内受阻全反射的能流模型,并且发现增大或减小两块棱镜的间距d,棱镜空气分界面上反射波束发生的Goos-Hnchen(GH)位移和Imbert-Fedorov(IF)位移也随之增大或减小。为了理论定量研究GH位移和IF位移,从经典电磁理论出发分析了有限Gauss平面波束通过对称双三棱镜后各分界面反射和透射场分布,从而基于能流模型计算出消失态Poynting矢量流中与位移有关的那部分能流。然后借助Renard能流法推出了新的GH位移和IF位移表达式。最后通过数值仿真得出位移随空气隙间距d的变化曲线,并将其与实验结论对比,结果表明所得的理论估算式是有效的。

It was well experimentally established in this paper that in a symmetry double-prism subjected to frustrated total internal reflection,the model for energy flux of reflected and transmitted beam is in agreement with Renard＇s theoretical model.In addition,we found that the Goos–Hnchen（GH）and Imbert-Fedorov（IF）shifts on the external interface of prism air must be uniformly varing with the distance d between the two prisms.Therefore,our researches have started with classical Fresnel-maxwell equations whose solutions were uesd to express the time-average Poynting vector flux associated with the GH and IF shifts.Then from the Renard＇s statement about GH shift and from the conservation of energy,the innovative evaluation expressions of the GH and IF shifts was derived as to a certain linearly polarized Gaussian beam in a double-prism symmetry structure.Eventually,we have depicted the shifts as a function of the distanced,and have obtained a good agreement between theory and experimental results.