Tunable infrared meta-absorber with single- and dual-absorption resonances

We present two perfect meta-absorber (PMA-1 and PMA-2) designs based on symmetrical/asymmetrical infrared metasurface. PMA-1 exhibits polarization-dependent characteristic. By changing the split gap and elevating the circumjacent metal bars of PMA-1, the resonances could be tuned 520 nm and 180 nm in TE mode, respectively. Furthermore, the absorption spectra could be switched between single-and dual-resonance by changing the incident polarization angle. For PMA-2, it shows polarization-independent characteristics. By changing the split gap and elevating the circumjacent metal bars of PMA-2, the resonances could be tuned 380 nm and 200 nm, respectively. These characteristics prove that the proposed PMA designs are very suitable for the uses in tunable programmable switching, optical communication, polarization-dependent/independent switching, filtering, and sensing applications.