Manipulation with Terahertz Wave Fronts Using Self-Complementary Metasurfaces

Here we numerically demonstrate the possibility to shape a wave front in the terahertz range using a self-complementary metasurface (SCMS) with spatial modulation. A circularly polarized incident wave passing through a SCMS causes two transmitted waves, a co- and cross-polarized. The co-polarized wave, in theory, has a complex transmission coefficient of 1/2 and keeps the same front shape as the incident wave, even if the metasurface is nonuniform. On the contrary, the cross-polarized wave obtains a phase, which can be locally controlled by geometric parameters of unit cells. We apply a phase holographic method to modify the shape of the cross-polarized wave in a desirable way while keeping the co-polarized wave unchanged.