Slow light propagation in stacked complementary metasurfaces at microwave frequencies

In this work, a metamaterial structure consisting of alternative layers of split-ring-resonators and complementary-splitring-resonators is studied numerically and experimentally. It is found that a delay of almost 3 orders of magnitude with respect to free-space of a microwave beam through this metamaterial structure can be achieved at th e first two transmission bands. The study is developed for 3 stacked functional layers, where one functional layer compresses one split-ring-resonators and one complementary-split-ring-resonators-metasurface.