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A multi-functional terahertz metamaterial with electromagnetically induced transparency (EIT) and broadband absorptions is proposed. The unit cell of the metamaterial is comprised of an E shape and a split-ring resonator on the top of the polyimide. For TE and TM polarization, the temporal coupled-mode theory reveals that the EIT effect arises from coupling two resonators. The transparent windows are experimentally demonstrated at 0.205 THz and 0.44 THz for the TM and TE polarization, respectively. When the vanadium dioxide ( VO 2) film is added to the bottom of the polyimide and works in the metallic state, the metamaterial could absorb electromagnetic waves in the broadband for the two polarizations, even in the case of oblique incidence. For the TE polarization, the relative bandwidth of the absorption over 60 % absorptance is 119.8 % in the range of 0.307 THz–1.225 THz. Meanwhile, for the TM polarization, the bandwidth over 60 % absorption is 68.8 % within the range of 0.52 THz–1.065 THz. The proposed multi-functional terahertz metamaterial can be widely used in sensing technology, optical storage, stealth technology, and other fields in reality. [ABSTRACT FROM AUTHOR]

In this paper, we report a new and generic method for all-dielectric resonators operating at terahertz (THz) frequencies based on polymer/ceramic composite particles. In this method, the polymer solution is added into ceramic powders (strontium titanate) and prilling technology is employed to make them become polymer/ceramic composite micro particles. The prepared micro particles are then assembled as single-layer all-dielectric resonators. By using a THz time-domain spectrometer, we find that various Mie resonances can be induced in these all-dielectric resonators. It is also demonstrated that the permittivity of the composite particles can be improved by being sintered at proper temperatures, thereby provides a new way for ceramic all-dielectric resonators in THz range. This method, free from complex process, time-consuming, expensive equipment, and clean room, provides a generic method for high-throughput and low cost THz all-dielectric resonators, which is promising for developing potential applications in wide-bandwidth THz devices. [ABSTRACT FROM AUTHOR]