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This paper proposes a vanadium dioxide metamaterial-based tunable, polarization-independent coherent perfect absorber (CPA) in the terahertz frequency range. The designed CPA demonstrates intelligent reconfigurable switch modulation from an ultra-broadband absorber mode to a dual-band absorber mode via the thermally controlled of VO2. The mode of ultra-broadband absorber is realized when the conductivity of VO2 reaches 11850 S/m via controlling its temperature around T = 328 K. In this mode, the CPA demonstrates more than 90% absorption efficiency within the ultra-wide frequency band that extends from 0.1 THz to 10.8 THz. As the conductivity of VO2 reaches 2×105 S/m (T = 340 K), the CPA switches to a dual-band absorber mode where a relatively high absorption efficiency of 98% and 99.7% is detected at frequencies of 4.5 THz and 9.8 THz, respectively. Additionally, using phase modulation of the incident light, the proposed CPA can regulate the absorption efficiency, which can be intelligently controlled from perfect absorption to high pass-through transmission. Owing to the ability of the proposed CPA to intelligently control the performance of light, this study can contribute towards enhancing the performance of stealth devices, all-optical switches and coherent photodetectors.

In this paper, we demonstrate a dual narrow‐band perfect metamaterial absorber for optical communication, where a silicon nano‐disk array is placed on a thin gold film separated by a dielectric layer. Numerical results reveal that dual narrow‐band perfect absorption peaks, which are attributed to waveguide mode and magnetic dipole resonance mode, are achieved at 1310 and 1550 nm, respectively. The results show that the absorption of the two peaks is higher than 99% under the normal incidence of both TE and TM polarizations and the bandwidth is 5 and 15 nm, respectively. Moreover, the absorption peak at 1310 nm can be independently tuned by varying the thickness of the dielectric layer. These findings imply that the proposed absorber can be used in the field of optical communication, frequency‐selective photodetection, and intersatellite laser communication.