| Summary: | 碩士 === 國立臺灣大學 === 應用力學研究所 === 101 === Metamaterails already played a very important role in the tools uesd by people. Humans usually obtain some special properties from designing artificial structure rather than composition, using small inhomogeneities to achieve effective macroscopic behavior. Due to the advancement of the nanotechnology, the study of the Goos-Hanchen shift becomes popular disquisition.
The Goos-Hanchen shift of reflection of a electromagnetic beam wave from an interface between two media, where the reflection coefficient’s phase changes with the change of incident angle is known to be accompanie by a small lateral shift in the plane of incidence. The phenomena has also been interpreted as a proof of the existence of such a flux of engery parallel to the surface inside the incident media. The direction of the GH shift is equal to the direction of a flux of engery on the interface. The phoenomena can be applied to the Goos-Hanchen shift surface plasmon resonance sensor, Optical temperature sensing based on the Goos-Hanchen effect…etc.
This thesis mainly investigates the apparent GH shift in the Metamaterails. In the first , we can use the anistropic medium rotating an angle to bring out the sysmmetrically oriented medium. By applying Finite Element Method(FEM) and appropriate Boundary Conditions (BCs), we can simulate Maxwell wave equation to get the dispersion relation.It can classify this metamaterails as two conditions. One is the discriminant of the dispersion relation is greater than zero,which the dispersion curve is an ellipse ,and the GH shift will be obvious at the incident angle near critical angle.The other is the discriminant of the dispersion relation is less than zero, which the dispersion curve is a hyperbola ,and the GH shift is obvious at the incident angle near critical angle. And then ,the GH shift of reflected beam wave at the incident angle near Brewster angle is also obvious ,and there are postive and negative shift. In the last, by applying FEM ,we can simulate the Gaussian Beam Wave to proof the Goos-Hanchen shift at the incident angle near critical angle and brewster angle in the sysmmetrically oriented medium.
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