Electromechanically perfect metamaterial absorber with ultrahighly polarization dependence on infrared sensing and imaging characteristics

• An electromechanically perfect metamaterial absorber (EPMA) is presented. • EPMA shows perfect absorptivity and exhibits ultrahigh polarization-dependent sensing characteristics. • Resonances exhibit a highly linear relationship (R 2 > 0.99). • Sensitivities are 2.0 μm/RIU in TE mode and 1.6 μm/RIU in TM mode. • By controlling each EPMA pixel, it can be used in the IR imaging application. We present a design for an electromechanically perfect metamaterial absorber (EPMA) that exhibits perfect absorptivity and ultrahigh polarization-dependent sensing characteristics. EPMA is composed of a tunable T-shaped resonator (TSR) on a SiO₂/Au/Si substrate. By precisely tuning the effective lengths of the TSR’s cantilevers, the resonant wavelengths of EPMA can be adjusted from 3.833 μm to 6.358 μm in transverse electric (TE) mode and from 2.614 μm to 6.689 μm in transverse magnetic (TM) mode. Moreover, the resonant wavelengths exhibit a highly linear relationship (R 2 > 0.99) when EPMA is exposed to the surrounding medium with different refractive indices. The sensitivities are up to 2.0 μm/RIU in TE mode and 1.6 μm/RIU in TM mode, respectively. Due to the EPMA configuration being asymmetrical, it shows polarization-dependent characteristics. It can be dynamically tuned and then control the resonant absorptivity. By converting the absorptivity of resonances into digital logic signals for controlling EPMA pixels, it can be used in the infrared (IR) imaging application. The proposed EPMA design exhibits great potential in the sensing, detection and imaging applications in the mid-IR wavelength range. Electromechanically perfect metamaterial absorber using T-shaped resonator with ultrahighly polarization dependent characteristics for infrared sensing and imaging applications.