Sequential trapping of single nanoparticles using a gold plasmonic nanohole array

TL;DR

This paper demonstrates the use of a gold nanohole array to trap single nanoparticles with high stiffness at low laser intensities, enabling precise control for lab-on-a-chip applications.

Contribution

It introduces a novel plasmonic nanohole array capable of trapping individual nanoparticles with high precision and low power, matching experimental results with simulations.

Findings

High trap stiffness of ~0.85 fN/(nmmW) at low laser intensity

Successful trapping of 30 nm polystyrene nanoparticles

Potential for arranging multiple particles in predefined patterns

Abstract

We have used a gold nanohole array to trap single polystyrene nanoparticles, with a mean diameter of 30 nm, into separated hot spots located at connecting nanoslot regions. A high trap stiffness of approximately 0.85 fN/(nmmW) at a low incident laser intensity of ~0.51 mW/um2 at 980 nm was obtained. The experimental results were compared to the simulated trapping force and a reasonable match was achieved. This plasmonic array is useful for lab-on-a-chip applications and has particular appeal for trapping multiple nanoparticles with predefined separations or arranged in patterns in order to study interactions between them.