Influence of the interaction between metal particles on optical properties of Ag-Si3N4 composite films. II. Two-particle approximation

The interaction between metal particles was calculated based on the discrete dipole method. The calculated results revealed that the multiple interactions in a collection of metal particles are dominated by the interaction between the neighboring particles. Thus, a two-particle approximation was deduced and applied to estimate the optical absorption and near-field enhancement property of Ag-Si3N4 composite films. The calculated results indicated that the interaction between Ag particles will induce extra absorption near the surface plasmon resonance peak and improve the near-field enhancement property of composite films. Calculated results were consistent with the experimental results.