▎ 摘　　要

A metal-graphene hybrid metasurface is proposed and numerically investigated for active tailoring of slow light in the terahertz (THz) regime. In the unit cell of the metasurface, four mirror-symmetrically arranged aluminum split ring resonators (SRRs) form the bright-dark-dark-bright mode coupling and exhibit a strong electromagnetically induced transparency (EIT) resonance characteristic. With monolayer graphene placed under the dark SRRs, both the transmission amplitude of EIT resonance and the group delay within the transparency window can be continuously tuned via shifting the Fermi level of graphene. Further theoretical analyses reveal that the active modulation arises from the increasing damping rate of the dark SRRs due to the recombination effect of the conductive graphene. The proposed metasurface provides an effective approach to tailoring the slow light effect and will find important applications in active functional devices for future THz wireless communications. (C) 2019 Optical Society of America