Slowing down light using terahertz semiconductor metamaterial for dual-band thermally tunable modulator applications.

Compared to the neighboring infrared and microwave regions, the terahertz regime is still in need of fundamental technological advances. We have designed a terahertz (THz) semiconductor metamaterial (MM) waveguide system, which exhibits a significant slow-light effect, based on a classical electromagnetically induced transparency phenomenon. The potential of MMs for THz radiation originates from a resonant electromagnetic response that can be tailored for specific applications. By appropriately adjusting the distance between the two radiative and nonradiative modes, a flat band corresponding to a nearly constant group index (of the order of 4924) in the THz regime can be achieved. Finite-difference time-domain simulations show that the incident pulse can be slowed down. The proposed device from a paucity of naturally occurring materials has useful applications in electronic or photonic properties at terahertz frequencies. This proposed compact configuration may find potential applications in plasmonic slow-light systems, optical buffers, and thermal and electromagnetic modulating applications and temperature sensors.