General approach to the synthesis of perfectly refractive metasurfaces

In this presentation we will introduce and discuss a general approach to the synthesis of metasurfaces for full control of reflected and transmitted fields. The method, which is applicable for any linear metasurface, is based on the use of an equivalent Z-matrix, connecting the tangential field components at the two sides on the metasurface. Finding the impedance matrix components, we are able to understand what physical properties of metasurface are needed in order to realize the desired response. Furthermore, we can find the required polarizabilities and/or susceptibilities of the metasurface unit cells and design the cell structures. In particular, we will discuss metasurfaces for perfect refraction into an arbitrary direction, explain possible alternative physical realizations and reveal the crucial role of bianisotropic coupling for design of perfectly matched metasurfaces for transmission control.