Dielectric resonance,local field distribution,and optical response in 3D resonant composites

We extend the Greens function formalism in a binary 2D composite to 3D. Using the formalism, we investigate the dielectric resonances, local-field distribution, and effective linear optical responses for one-bond, two-bond and three-bond clusters, as well as for various disordered composites. Due to the different values of Greens function in 2D and 3D, for the same cluster, the values of the dielectric resonances in 3D are smaller than those in 2D, but the fields are more localized than those in 2D. The sum rule of dielectric resonance in three-component composites is extended to d dimensions. For the same resonance, the intensity of the local-field in 3D is also weaker than that in the 2D case, but the fields are more localized than those in 2D. For the disordered composites in 2D and 3D, inverse participation ratios (IPR) with q = 2 are used to represent the localization of the field. When we increase the concentration of impurity bonds, a blue shift of IPR peaks occurs in 3D, while in 2D, these peaks are very stable. Finally, both for 2D and 3D disordered composites, the absorption range broadens with increasing impurity concentration, and a red shift of the absorption peak is observed in 3D.Received: 19 August 2004, Published online: 14 December 2004PACS: 77.84.Lf Composite materials - 42.65.-k Nonlinear optics