Ultra-Broad and Angle-Sensitive Terahertz Absorber

In this work, we demonstrated an ultra-broad terahertz absorber based on graphene metamaterial on SiO ₂ substrate which is sensitive to incident angle. The absorption performance can be changed by tuning the Fermi level of graphene. Nearly perfect peak absorption was demonstrated at broad terahertz frequency (1.3 ~2.2 THz, absorption > 0.99) with Fermi energy of 0.6 eV and graphene width of 13 um. Moreover, the absorber is sensitive to incident angle, indicating the potential applications in angle-sensing.