Strong Slow-Light Effect For A Hexagonal Graphene Coupled Metasurface In Terahertz

Exploring higher group index has great benefits in the application of plasmonic slow-light devices. A hexagonal graphene coupled metasurface is proposed for realizing dual plasma induced transparency(dual-PIT) in terahertz through finite-difference time-domain (FDTD) method. The results show that dual-PIT can be effectively tuned by Fermi levels, carrier mobilities, and polarization angles. Moreover, the group index can be as high as similar to 2553. These results may pave the way for the design of slow-light devices.