Angular momentum radiation from current-carrying molecular junctions*

We study the radiation of angular momentum (AM) from current-carrying molecular junctions using the nonequilibrium Green’s function method. The dependence of the the radiation on the molecular geometry is taken into account with a real-space tight-binding model coupled to the electromagnetic field. We study the relation between rotational symmetry of the molecule and the light radiation. We analyze the resonant effects when the applied bias crosses over the energy levels of the molecule. Our study maybe useful for generating radiation with AM from molecular junctions by simply applying an electrical bias.