Measuring storage and loss moduli using optical tweezers: broadband microrheology

TL;DR

This paper introduces a method using optical tweezers and a generalized Langevin equation to measure the broadband viscoelastic properties of complex fluids, covering a wide frequency range.

Contribution

It presents a novel experimental procedure for broadband microrheology with optical tweezers, enabling comprehensive measurement of viscoelastic moduli.

Findings

Successful measurement of storage and loss moduli across a broad frequency spectrum

Application of generalized Langevin equation to relate particle trajectories to fluid properties

Enhanced capability for microrheological analysis using optical tweezers

Abstract

We present an experimental procedure to perform broadband microrheological measurements with optical tweezers. A generalised Langevin equation is adopted to relate the time-dependent trajectory of a particle in an imposed flow to the frequency-dependent moduli of the complex fluid. This procedure allows us to measure the material linear viscoelastic properties across the widest frequency range achievable with optical tweezers.