Year: 2019
Type: article
Abstract: Optical tweezers are powerful tools to trap, transport, and analyse individual nano-objects at dilute concentrations. However, it is still challenging to manipulate isolated single nano-objects in dense target environments with various kinds of materials, such as in living cells and mixtures of nanocolloids. In the present work, we have succeeded in the selective trapping of a few gold nanoshells with specific sizes and sweeping others out completely, only by irradiating the dense colloidal suspension of gold nanoshells with a focused near infrared continuous-wave (CW) laser. This was achieved by an interplay between optical gradient- and thermophoretic forces: while the gradient force traps the targets at the focal spot, the thermophoretic force pushes others out from the focal spot. The distance between the trapped targets and the separated others was longer than 20 μm, allowing us to measure plasmonic scattering spectra of the trapped targets at a single-nanoparticle level. The present method paves a way for manipulating and analysing single nano-objects in dense mixtures of targets and various kinds of materials.
Source: Nanoscale
DOI: 10.1039/c9nr05052c
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: G1249109571, Pattern formation and selective transport of tiny particles using a flow in a nanoscale interface, Dynamical flow control of nanoparticles by machine learning and its application to single molecule identification technologies, Controlling flow fields on a nanometric scale via plasmonic heating of gold nanoparticles, G5446905401, G7220917659, Single-nanomaterial absorption spectroscopy based on photomechanical response, G8652254039
OpenAlex ID: W2966599657