Ultra-broadband electromagnetically induced transparency using tunable self-asymmetric planar metamaterials

We numerically and experimentally demonstrate a tunable electromagnetically induced transparency (EIT)-like spectral response in a self-asymmetric planar metamaterial in microwave region. This EIT-like physical mechanism is characterized by magnetic dipole coupling induced transparency, which is different from classical properties of EIT-like phenomenon. Our proposed system can be better explained by making an analogy to three-level Lambda-type system. Further study also revealed that an ultra-broadband transparency window with the maximum bandwidth up to 7.8 GHz, extending from 6.1 GHz to 13.9 GHz, could be realized by simply adjusting the depth of the structure. (C) 2013 AIP Publishing LLC.