Effective medium theory applied to colloidal solution of gold nanoparticles and alternating gold-silica multilayer thin film composites

Optical modeling of multilayer thin films constructed with oppositely charged nanoparticles help us to understand phenomenon such as surface plasmon resonance,absorbance,transmittance and reflectance. this work reports the application of maxwell-garnett effective medium theory in quasi-static limit to colloidal suspensions consisting of host material silica and the inclusion material -gold nanoparticles. layer-by-layer deposition method was used to self-assemble these nanoparticles to build multilayer composite films. by varying the number and thickness of the layers and the size and spacing of the metal inclusion,a facilitative optical design is modeled to build multilayers of nanosized materials targeted for desired applications.