Generalized Snell’s Law and Its Verification by Metasurface

The generalized Snell’s law derived based on Fermat’s principle and the boundary conditions of continuity are introduced in this paper. The 3D format of generalized Snell’s law is also demonstrated. The generalized Snell’s law is proved by metasurface, which is composed of quasi-periodical square patch units. The establishment of model for simulation is introduced and the anomalous reflection of metasurface is verified. A method for structure simplification is proposed by further analyzing the generalized Snell’s law and verified. The simulated results show that for normal incident EM wave, the anomalous reflection angle is 46°, which is approximate with the theoretical result. Furthermore, the anomalous reflection angle does not change when reducing the kinds of units from 8 to 2, proving that the number of kind of chosen units does not affect the anomalous reflection angle when the length of super unit remain unchanged.