Plasmonic Lattice Mode Formed by Ag Nanospheres on Silica Pillar Arrays

TL;DR

This paper presents a method to form and optimize plasmonic lattice modes in Ag nanosphere arrays on silica pillars, enhancing their optical properties for potential applications.

Contribution

It introduces a novel structure with Ag nanospheres on silica pillars and demonstrates how pillar height influences plasmonic lattice mode formation and transmittance.

Findings

Plasmonic lattice mode can be formed around the array period.

Increasing SiO2 pillar height weakens near-field coupling.

Optimized lattice modes improve transmittance control.

Abstract

A method to form the plasmonic lattice mode of periodic metallic nanoparticle arrays is presented. In the arrays, each Ag nanosphere is on the top of a SiO2 nanopillar which sits on a quartz substrate. The simulated results show that, in the wavelength range around the period of the arrays, the plasmonic lattice mode can be formed. The transmittance of the structure varies rapidly from the maximum to the minimum in a narrow wavelength band. This is attributed to the wavelength-dependent diffracted waves generated by the periodic arrays and the weak near-field coupling between Ag nanospheres and the quartz substrates. Increasing the height of SiO2 nanopillars can weaken the near-field coupling between Ag nanospheres and the quartz substrates, and lead to the greater effects of the diffracted waves on the transmittance. As a result, the plasmonic lattice mode can be optimized. This method provides a possible way to promote the application of the plasmonic lattice mode.