A Novel Multilayer Broadband Terahertz Metamaterial Absorber Based on Three- Dimensional Printing and Microfluidics Technologies

The manufacturing of 3-D metamaterials remains a major challenge and the narrow-band absorption characteristics limit the practical applications of terahertz (THz) metamaterial absorbers. To this end, we propose to combine the 3-D printing technology with the microfluidics technique to fabricate a THz metamaterial absorber with a relative broadband (∼0.3 THz) under 1 THz. Here, the absorber consists of embedded multilayer disk microfluidics channels stacked vertically within the resin and filled with liquid metal. It has been demonstrated that the experimental results agree well with the simulations, where the absorber exhibits polarization sensitive and incident angle insensitive in the frequency range from 0.25 to 0.6 THz. The proposed method enables the fabrication of THz metamaterial devices with complex structures in a fast, simple, and low-cost way, which is no longer limited to the conventional photolithography processes. This approach effectively stimulates many potential applications in emerging THz technologies, such as sensing, imaging, and wireless communications.