title: Accounting for inertia effects to access the high-frequency microrheology of viscoelastic fluids.
abstract: We study the Brownian motion of microbeads immersed in water and in a viscoelastic wormlike micelles solution by optical trapping interferometry and diffusing wave spectroscopy. Through the mean-square displacement obtained from both techniques, we deduce the mechanical properties of the fluids at high frequencies by explicitly accounting for inertia effects of the particle and the surrounding fluid at short time scales. For wormlike micelle solutions, we recover the 3/4 scaling exponent for the loss modulus over two decades in frequency as predicted by the theory for semiflexible polymers.
authors.affiliation: Departamento de Física de Materiales, Universidad Nacional de Educación a Distancia (UNED), Madrid 28040, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Domínguez-García
authors.affiliation: Department of Physics, University of Fribourg, 1700 Fribourg Perolles, Switzerland and LS Instruments AG, Passage du Cardinal 1, CH-1700 Fribourg, Switzerland.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Cardinaux
authors.affiliation: Laboratory of Physics of Complex Matter, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Elena
authors.initials: E
authors.lastname: Bertseva
authors.affiliation: Laboratory of Physics of Complex Matter, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: László
authors.initials: L
authors.lastname: Forró
authors.affiliation: Department of Physics, University of Fribourg, 1700 Fribourg Perolles, Switzerland.
authors.forename: Frank
authors.initials: F
authors.lastname: Scheffold
authors.affiliation: Laboratory of Physics of Complex Matter, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Jeney