Analysis and synthesis of bianisotropic metasurfaces

Methods to analyze and synthesize bianisotropic metasurfaces are developed. This work enables complete control of the polarization of an electromagnetic wavefront for the first time. First, a simplified homogenization procedure is reported that can model the reflection and transmission coefficients of an arbitrary bianisotropic metasurface. Next, a systematic method to realize an arbitrary bianisotropic response is demonstrated. It is analytically shown that cascading patterned metallic sheets (anisotropic sheet admittances) offers significant control of the electric, magnetic, and chiral responses. Each sheet is individually designed to have a full tensor sheet admittance. To demonstrate the design procedure, two exotic polarization transformations with near-optimal performance are experimentally demonstrated for the first time: polarization rotation and asymmetric circular transmission.