Theoretical And Experimental Investigation Of Enhancement Of Goos-H(?)nchen Shift

Goos-Hanchen (GH) Shift plays an important role in the field such as optical communication, near field measurement and so on. However, this shift of reflected light beam that occurs in a single-interface is less than one wavelength and difficult to measure. Therefore, its application is impeded for a long time. Recently, the enhancement of Goos-Hanchen Shift becomes one of the focus in this field. Firstly, the development, the main theoretical approachs such as the stationary phase method and the nenergy flux method are introduced. Based on the above description, the Goos-Hanchen shift of the refletected and transmitted light beam in the film-coated dielectric prism configuration, a single film-coated symmetric double-prism configuration and the weakly active dielectric film coated prism configuration is thoroughtly investigated by the stationary phase method. The dependence of the Goos-Hanchen shift on the incident angle, the thickness of thin film and the thickness of air gap is discussed separately. It is shown that the Goos-Hanchen shift of the discussed configuration are resonantly enhanced with respect to the incicent angle or the the thickness of the thin film, and its magnitude can be of one or two order of wavelength when the angle of incidence is larger than the critcal angle for total reflection at prism-vacuun interface and is small than but close to the critical angle for reflection at the prism-film interface. In the single film-coated symmetric double-prism configuration when the thin film is coated onto the surface of the first prism, the shift of transmitted beam is about half the shift of reflected beam. In the single film-coated symmetric double-prism configuration when the thin film is coated onto the surface of the second prism, the shift of reflected beam is negative near the resonant point. In the weakly active dielectric film-coated prism configuration, many resonant peak of the giant negative shift can be achieved and easiely measured. In order to varify the theoretical prediction, microwave experimental setup of the reflected beam shift is designed and the shift is measured. the experimental errors and the Means to reduce them is also discussed. For linear polarized microwave beam, The experimental measurements are in good agreement with theroretical calulations.