Quantum size and nonlocal effects in the electromagnetic properties of small metallic spheres

Abstract
The electromagnetic properties of small spheres are analyzed by including quantum size effects and nonlocal properties of the response function. Our model neglects the diffuseness of the surface electron charge but includes effects associated with the surface roughness, which is assumed to randomize the electrons scattering off the surface. Quantum size and roughness effects are discussed and we analyze under what specific conditions they can appear.