Bifunctional terahertz meta-device with switchable properties between dual-narrowband absorption and broadband absorption

provides the ability to independently modulate the absorbance of these two types of operating modes. The physical mechanism of the bifunctional terahertz absorption meta-device is elucidated through impedance matching theory and surface electric field distributions in different operating modes. Both of these operating modes have the characteristic of large-angle tolerance, and further research has been conducted on the use of dual-narrowband absorption mode for sensing applications. The merits of the aforementioned meta-device, encompassing structural simplicity, integration of multiple functions and dynamic tunability, are noteworthy and may stimulate interest in the development of powerful, compact and practical integrated terahertz components.