Double-layer broadband perfect metamaterial absorber and its potential for refractive index sensing

摘要

A simple structured broadband perfect metamaterial absorber (PMA) for visible-infrared spectrum is proposed. The PMA composed of a two-dimensional vanadium (V) cylinder array coated with a film of TiO2 and a V substrate is designed using finite-difference time-domain method. Theoretical simulation results show that the PMA exhibits nearly perfect absorption in a wide waveband region from 400 to 1600 nm. The PMA has another potential for refractive indices sensing when it is immersed in different surrounding dielectrics such as liquid and solution. Furthermore, a PMA sample is fabricated and the spectral responses of the PMA sample are measured. Owing to the good consistence of theoretical simulation results and experimental ones, the novel characteristics of the proposed PMA are experimentally demonstrated.