Tunable narrowband metamaterial perfect absorber with single absorption peak

Abstract

A tunable narrowband metamaterial perfect absorber (NMPA) with single absorption peak at both normal incidence and oblique incidence is proposed. The spectral responses of the designed NMPA are calculated using finite-difference time-domain (FDTD) method. By using an Ag guided-mode resonance grating layer with great fill factor, the designed NMPA exhibits single resonance peak, which is converted to heat due to the strong surface plasmon resonance around the Ag grating and the Ag substrate. An NMPA sample is fabricated and the spectral responses are measured to verify the theoretical results. The experimental results are consistent with the theoretical ones.