Numerical Study of an Ultrabroadband, Wide-Angle, Polarization-Insensitivity Metamaterial Absorber in the Visible Region

We propose and numerically investigate an ultrabroadband metamaterial absorber (MA) formed of a periodic array of metallic-dielectric multilayered conical frustums for use in the visible regime. The bandwidth and absorption performance of the proposed absorber can be controlled by varying structural parameters such as the tilt angle and lattice constant. The absorption efficiency of the proposed MA exceeds 80% in a wide bandwidth from 474.4 nm to 784.4 nm and is retained at large angles of incidence up to 65 degrees. Furthermore, perfect polarization insensitivity is also obtained due to its rotationally symmetric structure. This excellent absorber performance makes the proposed MA a promising candidate for applications in the visible region.