Dynamically tunable electromagnetically induced transparency in a terahertz hybrid metamaterial

Highlights: • A tunable EIT resonance is demonstrated in a THz hybrid metal-graphene metamaterial. • The oscillator model and field distribution are calculated for coupling analysis. • The modulation mechanism is attributed to the recombination effect of graphene. • The well-controlled group delay is achieved for slow light applications. A novel mechanism to realize dynamically tunable metamaterial analogue of electromagnetically induced transparency (EIT) in the terahertz (THz) regime is proposed. By putting a monolayer graphene under the dark resonator, the amplitude of the EIT resonance in the metal-based metamaterial can be substantially modulated via altering the Fermi level of graphene. The amplitude modulation can be attributed to the change in the damping rate of the dark mode caused by the recombination effect of the conductive graphene. This work provides an alternative way to achieve tunable slow light effect and has potential applications in THz wireless communications.