Tunable terahertz plasmonic perfect absorber based on arrow-shaped InSb array

摘要

In this paper, a nearly perfect terahertz absorber for transverse magnetic (TM) polarization based on Arrow-shaped InSb array is proposed and numerically investigated. Incident wave at the Fabry-Perot resonant frequency can be totally absorbed into the narrow grooves between the two adjacent Arrow-shaped InSb arms. The absorption mechanism is theoretically and numerically studied by using the Fabry-Perot model and the finite element method (FEM), respectively. The absorption peak can be controlled by varying the temperature. Furthermore, a new absorption peak will emerge while breaking the symmetry of the Arrow-shaped InSb array. This tunable THz perfect absorber may find important applications in THz devices such as microbolometers, coherent thermal emitters, solar cells, photo detectors, and sensors.