Distinguishing dielectric materials using spatial Goos-Hänchen shift

Abstract

In this study, we have conducted experimental measurements of spatial Goos-Hanchen (GH) shifts of s and p polarized light reflected from two separate air-dielectric systems (Air-Si and Air-GaAs). Our objective is to demonstrate the method's capabilities in distinguishing materials with near identical and overlapping reflectivity curves. We have measured the spatial GH shift of light with λ = 594 nm reflected from Si, as well as the spatial GH shift of light with λ = 543 nm reflected from GaAs. From this, we have found that the peak shift of light reflected in Si was 904% larger compared to the peak shift of light measured in GaAs. We have also calculated the peak widths of the resonant peaks, showing a great peak width difference between the GH of light reflected from Si and GaAs. The measured differences in the quantities presented are large compared to the calculated quantity differences in the reflectivity of the materials. From these results, we have demonstrated that the method of measuring spatial GH shift demonstrates a more flexible method of optically distinguishing materials.