Graphene Terahertz Absorber Driven by Electric Dipole Resonance for Tunable Switching and Sensing

This paper presents a graphene‐based terahertz absorber. Five narrowband absorption peaks are achieved at 2.82, 4.91, 6.53, 8.05, and 8.99 THz, with an average absorption rate of 96.56%. The device exhibits polarization‐insensitive characteristics, maintaining stable absorption performance over incidence angles ranging from 0° to 60°. Dynamic tuning of the absorption peak frequencies is achieved by modulating the graphene Fermi level, and a five‐frequency synchronous optical switching functionality is demonstrated, achieving a modulation depth up to 95.95% and insertion loss as low as 0.013 dB. In sensing applications, the device demonstrates highly sensitive responses, with a maximum sensitivity of 2.0 THz/RIU. Through systematic mechanism analysis, it provides a novel approach for terahertz functional devices that combines practical utility with manufacturability.