A multifunctional terahertz device based on vanadium dioxide metamaterials that switches between ultra-broadband absorption and ultra-high-Q narrowband absorption

is transformed into the metallic state, the device achieves more than 90% ultra-broadband absorption in the range of 3.93 THz to 9.25 THz, and its broadband absorption properties originate from the electric dipole resonance. In addition, the performance of the device remains stable at different structural parameters. Compared to existing technologies, this design integrates dual functionalities in a single-layer hybrid structure, significantly reducing fabrication complexity.