Feasibility test on the analog configuration of electromechanical dimple-tip cantilever for the application of THz metamaterials

We numerically and experimentally developed a cantilever that provided both fast and analog actuation for THz metamaterials (MMs) by properly geometrizing a dimpled tip. Owing to its small size and light mass, the cantilever had a high mechanical resonance at 705 kHz. Cantilever arrays were fabricated with different tip gaps and integrated into a ladder-shaped MM (LS-MM). By changing the tip gap from 0.80 to 0.32 μm, the resonance of the transmittance spectrum changed from 1.235 to 0.795 THz, indicating that the reconfigurable LS-MM was capable of continuously tuning the resonance of the THz wave transmission with the tip gap. Additionally, the dimple served as an anti-stiction structure, providing the cantilever with a fabrication yield of 99.8%. This work shows a practical pathway to high-performance active metamaterials, which holds potential in advanced THz technologies such as 6G communications and fast imaging.