Shift of localized surface plasmon resonance in monolayer of small gold nanoparticles: Simulation predictions of interparticle coupling

Localized surface plasmon resonance of gold nanoparticle layer is investigated by the experiment as well as theoretical calculations. The limits of analytical models are illustrated for compact nanoparticle film revealing signify cant discrepancy between experimental and simulated results while the numerical calculations based on finite-difference time-domain using thin film optical parameters are shown as suitable. There it is shown that 3D finite-difference time-domain simulation can be replaced by 2D simulation without losing accuracy of the calculation of localized surface plasmon resonance. The dependence of the localized surface plasmon resonance wavelength on the nanoparticle size, separation as well as local dielectric constant of surrounding environment is presented and applied for the real nanoparticle size and separation distributions observed in the experiment. Tuning of plasmon resonance in a wide range is demonstrated as a promising way for further applications.