Oscillatory Optical Response of an Amorphous Two-Dimensional Array of Gold Nanoparticles

Abstract

The optical response of metallic nanoparticle arrays is dominated by localized surface plasmon excitations and is the sum of individual particle contributions modified by interparticle coupling that depends on specific array geometry. We demonstrate a so far unexplored distinct oscillatory behavior of the plasmon peak position, full width at half maximum, and extinction efficiency in large area amorphous arrays of Au nanodisks, which depend on the minimum particle center-to-center distance in the array. Amorphous arrays exhibit short-range order and are completely random at long distances. In our theoretical analysis we introduce a film of dipoles approach, within the framework of the coupled dipole approximation, which describes the array as an average particle surrounded by a continuum of dipoles with surface densities determined by the pair correlation function of the array.

Experimental verification and investigation of disks scattering slab modes in metal-dielectric heterostructures

“…It is well known that lattice modes can exist in metallic nanodisk arrays and will hybridize with the localized surface plasmons (LSPs) sustained by each of the metal disks17181920. However, such hybridized modes are totally different from DSFPMs, because in the THz regime real plasmons, including LSPs, do not exist in the metal disks, which are usually treated as PEC disks for THz wave.…”

Energy transport of surface phonon polaritons propagating along a chain of spheroidal nanoparticles

“…Considering that the coupling among individual resonances of each nanoparticle may guide surface electromagnetic fields along a chain of nanoparticles, these structures have been proposed as potential waveguides of both SPPs and SPhPs. The propagation [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] and energy transport [10,19] by SPPs propagating along chains of metallic nanoparticles have been widely investigated by many research groups, while analogous works dealing with SPhPs are scarce [20].…”

Plasmon‐Assisted Indirect Light Absorption Engineering in Small Transition Metal Catalyst Nanoparticles

“…The reason for not using the spectral dependence of the splitting factor, but instead the value at the LSPR peak, is a mismatch in the spectra between the measurements and calculations. This mismatch stems from interaction between the disks in the array which is not present for a single nanodisk as used in the simulations. Additionally, the deposited 5 nm Si 3 N 4 layer had a refractive index of 1.9 (ellipsometric measurements), which is smaller than the assumed value of 2 used in FDTD calculations (silicon nitride has a refractive index between 1.8 and 2.8 in the visible depending on the stoichiometry .…”