Terahertz 3D Components Made from Metamaterials

A realization of next-generation ultrafast wireless communication (6G) and security imaging in the terahertz waveband is a question of time because of the rapid development of terahertz oscillators. However, terahertz components have vet to be developed whereas components in the optical region and millimeter waveband provide sufficient support for technological and scientific progress. Here we produce a reflectionless metamaterial with an extremely high refractive index of 12.3 in the 0.3-THz band and apply it to a 3D phase delay component for high-performance gradient-index terahertz lenses. We also demonstrate a large-aperture robust polarizer with an extreme sensitivity of high extinction ratios below -50 dB consisting of a metamaterial with a large negative relative permittivity of -97.6. The 3D terahertz components utilizing unprecedented materials would contribute to the development of a future industry based on terahertz applications.