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arXiv · 2111.14989

Characterisation of Nanoparticle Size Distributions in a Fluid using Optical Forces

Kiana Malmir·William Okell·Aurélien A P Trichet·Jason M Smith
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Abstract

We introduce a method for analyzing the physical properties of nanoparticles in fluids via the competition between viscous drag and optical forces. By flowing particles through a microfluidic device containing an optical microcavity which acts as a combined optical trap and sensor, the variation of the rate of trapping events with the different forces can be established. A clear threshold behaviour is observed which provides a measure of a parameter combining the dielectric polarizability and the hydrodynamic radius. This technique could be applied in combination with other analytic techniques to provide a detailed physical characterisation of particles in solution.

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Kiana Malmir, William Okell, Aurélien A P Trichet, Jason M Smith. 2021-11-29. Characterisation of Nanoparticle Size Distributions in a Fluid using Optical Forces. https://arxiv.org/abs/2111.14989

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