Tunable electromagnetically induced transparency at terahertz frequencies in coupled graphene metamaterial*
Ding Guo-Wena), Liu Shao-Bina), Zhang Hai-Fenga),b), Kong Xiang-Kuna),c), Li Hai-Minga), Li Bing-Xianga), Liu Si-Yuana), Li Haib)
       
(a) Top view of the unit cell with dimensions. (b) Cross-section view and the normally incident excitation.