2017/05/24 by Guillaume Lavigne, Lavigne, Guillaume, Karim Achouri +7 · 1 citation
Materials Science · Engineering · #Metamaterials and Metasurfaces Applications #Advanced Antenna and Metasurface Technologies #Antenna Design and Analysis
paper · pdf · doi:10.48550/arxiv.1705.09286
Refraction represents one of the most fundamental operations that may be performed by a metasurface. However, simple phasegradient metasurface designs suffer from restricted angular deflection due to spurious diffraction orders. It has been recently shown, using a circuit-based approach, that refraction without spurious diffraction, or diffraction-free, can fortunately be achieved by a transverse metasurface exhibiting either loss-gain or bianisotropy. Here, we rederive these conditions using a medium-based - and hence more insightfull - approach based on Generalized Sheet Transition Conditions (GSTCs) and surface susceptibility tensors, and experimentally demonstrate two diffraction-free refractive metasurfaces that are essentially lossless, passive, bianisotropic and reciprocal.