Polarization-insensitive and wide-angle broadband nearly perfect absorber by tunable planar metamaterials in the visible regime

We present the design and analysis of a polarization-insensitive and wide-angle broadband nearly perfect absorber by planar metamaterial in the visible regime. The bandwidth of absorption spectrum can be effectively expanded by combining multiple resonant elements. The forming mechanisms of the broadband metamaterial perfect absorber (MPA) are also demonstrated by the hybridization of the plasmonic system. The resonance of the broadband MPA can be dynamically tuned by varying the intensity of the incident beam. This kind of all-optically tunable perfect absorber will help to overcome some of the limitations of customary designs developed so far.