Optical properties of core-shell particle composites. I. Linear response

The effective dielectric response of core-shell particle composites is calculated analytically and numerically in terms of the ellipsoidal Lorentz cavity. The particles are considered to be shape-distributed confocal ellipsoids. Both the one-dimensional and two-dimensional steplike shape distribution functions are examined. The results are illustrated by numerical calculations carried out for metal core particles coated with a dielectric shell.