Controlling the LSPR properties of Au triangular nanoprisms and nanoboxes by geometrical parameter: a numerical investigation

TL;DR

This study uses numerical simulations to explore how the geometrical parameters of gold triangular nanoprisms and nanoboxes influence their localized surface plasmon resonance (LSPR) properties, aiming to optimize their sensing capabilities.

Contribution

It provides a detailed numerical analysis of how aspect ratio and wall thickness affect LSPR sensitivity and FOM, identifying optimal geometries for sensing applications.

Findings

Refractive index sensitivity increases with aspect ratio and decreases wall thickness.

Optimal wall thickness maximizes the figure of merit (FOM) for sensing.

Triangular nanoboxes exhibit higher FOM than cubic nanoboxes due to shape effects.

Abstract

We have simulated the extinction spectra of Au triangular nanoprisms and nanoboxes by finite difference time domain (FDTD) method. It is found that the refractive index sensitivity increases linearly and near exponentially as the aspect ratio of nanoprisms increases and wall thickness of nanoboxes decreases. A sensing figure of merit (FOM) calculations shows that there is an optimum wall thickness for each edge length and height of the box, which makes them to be promising candidate for effective sensing applications. We have also shown that the higher FOM in triangular nanoboxes compared to the cubic nanoboxes and other solid structure is inherent in the shape of nanoparticles.