Electromagnetic response of a metamaterial with field-gradient-induced   transparency
  We investigate a dynamically controllable electromagnetically induced transparency-like metamaterial. The unit structure of the metamaterial consists of a low-quality-factor resonator and a high-quality-factor resonator. The field gradient of the incident electromagnetic wave in the transverse direction induces coupling between these two types of resonators and causes a transparency phenomenon. We present the simulation and experimental results for the dynamic control of the electromagnetic response. 
Yasuhiro Tamayama, Toshihiro Nakanishi, Yasuhiro Wakasa, Tetsuo   Kanazawa, Kazuhiko Sugiyama, and Masao Kitano
physics.optics