3D‐Printed Terahertz Metamaterial Microfluidic Chips for Dynamic Optofluidic Sensing and Imaging

Microfluidic chips integrated with 3D metamaterials face two major challenges: fabrication and packaging. Traditionally, the fabrication of these two components requires separate processes followed by bonding and packaging, which are both complex and costly. In this work, we unify the fabrication process of metamaterials and microfluidic chips through projection micro-stereolithography (PµSL) and liquid metal filling, eliminating the need for additional packaging steps. To demonstrate the versatility and compatibility of this approach, we designed two THz metamaterial-integrated microfluidic devices based on the chiral response of helical metamaterials: a THz fluidic sensing chip (TFSC) and a fluid-driven THz dynamic display chip (FTDDC), thereby establishing a novel all-fluidic platform for dynamic THz optofluidic sensing and imaging. TFSC employs a 3D-printed hollow sensing chamber, enabling dynamic and precise detection of ethanol–diesel fuel blending ratios. The FTDDC, on the other hand, realizes dynamic THz image display by modulating the local chiral response through the controlled flow of liquid metal and HCl solution in the microchannels. In conclusion, the metamaterial microfluidic chips fabricated via PµSL-based 3D printing not only overcome the technological limitations of conventional microfluidic design, fabrication, and integration, but also open new avenues for the exploration and application of fluid-driven terahertz metamaterials.