Dyadic Green's function for the electrically biased graphene-based multilayered spherical structures

Abstract

Dyadic Green's function for a multilayered spherical structure with alternating graphene-dielectric shells is extracted in this paper. To this end, the unknown expansion coefficients of the scattering superposition method are obtained by considering graphene local surface currents at the interface of two adjacent layers. To validate the formulas, the procedure of Mie scattering analysis employing our formulas is clarified and the extinction efficiencies of various graphene-based nanoparticles are computed. The possibility of using the proposed structure in the design of multi-band optical absorbers is discussed in detail. Moreover, a closed-form formula for obtaining the Purcell factor of a radial dipole emitter in the presence of a graphene-based layered sphere is introduced. The analysis is followed by an example illustrating the possibility of dual-band enhancement of the Purcell factor using a graphene-based core-shell particle. Finally, the procedure of calculating the energy transfer between the donor-acceptor pairs with arbitrary locations are clarified. The research can be potentially used in the fast and efficient analysis of a wide class of novel optical devices with the arbitrary source of excitation.