Graphene Metamaterial for High Absorption of Unpolarized Light over More Than Three Octaves of Bandwidth

Strong broadband absorption of unpolarized light in a large-area, thin film is important for photovoltaics, photodetectors, thermal emitters [1] and optical modulators. Graphene is a suitable material for absorbers, as its absorption bandwidth is very large, but a single layer of graphene absorbs only 2.3% [2].