Thermal broadband tunable Terahertz metamaterials

A thermally tunable metamaterial comprising a periodic array of metallic split-ring resonators with an embedded semiconductor has been proposed. The resonance frequencies of the metamaterial are demonstrated to be continuously tuned in the terahertz regime by increasing the temperature. The tunability is attributed to the temperature-dependent permittivity of the embedded semiconductor and well analyzed by an equivalent capacitor–inductor model. The proposed designs ensure broadband thermally tunable terahertz devices.

Research Highlights
► Semiconductors have a significant advantage in that their relative permittivity can be modified by changing the temperature.
► Metamaterials comprising semiconductor constituents thus enable a broadband thermal tuning of resonance frequency in the terahertz regime.
► A large blueshift of resonance frequency in our proposed structures as much as ~ 65% can be implemented with increasing temperature.
► The shifts of resonance frequency obtainable are quite consistent with the analytical predictions based on an equivalent LC model.