Optical conductivity and far-field radiation of silicene

Silicene is a silicon analogue of graphene. From symmetry considerations, we develop the matrix of Hamiltonian, including spin-orbit coupling in silicene. This work analyzes the heat and angular momentum radiation from silicene through the theory of far-field radiation and optical conductivity. We discuss the relation between the radiation and spin-orbit coupling parameters. Our results show the effects of different parameters, such as temperature and sublattice potential, on optical conductivity and radiation of silicene. In particular, the threshold frequency of optical conductivity causes the appearance of the second peak in energy radiation spectrum. We also find that the ratio of the perpendicular electric field to the intrinsic spin-orbit coupling is related to the strength of angular momentum radiation, which may promote the application of silicene.