Optical absorbance in multilayer two-dimensional materials: Graphene and antimonene

Antimonene, one of the group V elemental monolayers, has attracted intense interest due to its intriguing electronic properties. Here, we present the optical absorption properties of atomically flat antimonene for which the directional bonds between Sb atoms appear to be analogous to C-C bonds in graphene. The results, based on first-principles density functional theory calculations, predict the absorbance in multilayer antimonene to be comparable or higher than that calculated for multilayer graphene. Specifically, the IR absorption in antimonene is significantly higher with a prominent band at about 4 mu m associated with the dipole-allowed interband transitions. Furthermore, a strong dependence of absorbance on topology is predicted for both antimonene and graphene which results from the subtle variations in their stacking-dependent band structures. Our results suggest multilayer antimonene to be a good candidate material for optical power limiting applications in the IR region.