The optical properties of four triatomic all-dielectric metamaterial structures composed of TiO2 media are investigated numerically. Two symmetrical metamaterial structures with dark-bright-dark coupling mode and bright-dark-bright coupling mode can enhance and cancel the original single EIT transparent window, respectively. And double EIT transparent windows were observed in the other two asymmetric structures with the bright-bright-dark and dark-dark-bright constructions. This means that the EIT effect can be controlled by the changing the ne...
