Additive manufacturing of metamaterials in 6G communication based on ink-jet printing

The conventional approaches to sub-terahertz metamaterial (MM) fabrication, which rely heavily on lithography and etching techniques, pose significant challenges in terms of costs, material consumption, and the complexity of the processes. To address these issues, there is an urgent need for enhancing efficiency and environmental sustainability in MM production. Thus, we explore a rapid customization approach utilizing ink-jet printing technology (IJPT) to achieve additive manufacturing of MMs for signal selectivity in 6G communication. The proposed MMs comprise two primary units: one double-split ring (DSR) hollowed MM (MM-1) is designed to realize band-pass filtering, while the other dumbbell-shaped MM (MM-2) has a band-stop filtering response. By adaptively adjusting the nozzle voltage between 14 and 22 V, we ensure a consistent line width of approximately 200 μm, enabling an effective frequency selection characteristic within the sub-terahertz band. Through altering the scale factor of MM-1, we achieve a frequency tuning from 61.00 to 72.75 GHz, with an optimal Q value of 27.71. Similarly, the periodic size of MM-2 results in a frequency shift from 76.58 to 91.10 GHz, with a maximum Q value of 11.26. Measured and simulated results for the MMs are in close agreement. The experimental results validate the feasibility of IJPT as an effective method for processing sub-terahertz MMs, emphasizing the great potential for optimizing6Gcommunication systems and signal filtering applications.