Enhanced absorption of graphene monolayer with a single-layer resonant grating at the Brewster angle in the visible range

One method for enhancement and manipulation of light absorption with monolayer graphene covered on a single-layer guided mode resonant Brewster filter surface is demonstrated. By means of the rigorous coupled-wave analysis method, the effect of geometrical parameters on the optical response of the structure is investigated. It is possible to achieve a maximum absorption of 60% at the Brewster angle; dual-band optical absorption can also be realized when the depth of the grating is increased. The situation of oblique incidence for TM polarization is studied as well; the absorption property can be controlled by adjusting the incident angle without changing the structural parameters. The proposed structure has the advantage of more free geometry parameters compared to the graphene disk and ribbon, so the absorption could be tuned more flexibly.