“Bottom-up” three-dimensional metamaterials at terahertz frequencies

In this paper, we present our recent progress on three-dimensional (3D) metamaterials at terahertz (THz) frequencies. Using a “bottom-up” multilayer electroplating technique, a flexible and a broadband tunable metamaterial was fabricated and characterized. In agreement well with numerical simulations, characterization on these 3D metamaterials by THz time domain spectroscopy (THz-TDS) indicates excellent performance of 3D metamaterials in manipulating electromagnetic waves. The successful fabrication of these 3D structures from well-defined building blocks provides a new pathway towards “bottom-up” 3D metamaterials for potential applications at THz frequencies.