Validity domain and limitation of non-retarded Green's tensor for electromagnetic scattering at surfaces

This work gives a detailed derivation of the non-retarded dyadic Green's te nsor associated with surfaces in the quasistatic approximation. The derivat ion is made from a rigorous model where the dyadic is expressed as Sommerfe ld integrals. We then assess the domain where this approximation can be use d for scattering calculations on surfaces by comparing rigorous and non-ret arded solutions. Implications of this work for scattering calculations in n ear-field optics are finally discussed. (C) 2000 Elsevier Science B.V. All rights reserved.