Influence of the interaction between two Ag nanoparticles on optical properties of Ag/PGMEA nanocomposite materials

Abstract

We report local electric field calculations in Ag/PGMEA nanocomposite materials using the dipole discrete approximation. We employ calculation and simulation to show that the nanoparticle radius and the interparticle distance could control and tune the surface plasmon resonances, which influence the extinction spectra and the near-field enhancement of Ag/PGMEA nanostructures. With decreasing interparticle distance, the near-field coupling between particles will induce the shift of surface plasmon resonance peak and improve the near-field intensity. With increasing radius (r), the resonance wavelength peak is red-shifted because of the interaction between two Ag nanoparticles. At 449 nm, the highest near-field enhancement factor obtained in the center of the gap was 30.5 for two interacting Ag nanoparticles of r = 11 nm with a gap of 5 nm.

Keywords:

• local electric field
• surface plasmon resonance
• discrete dipole approximation
• nanocomposite