Diego Baresch

CNRS - University of Bordeaux · Mechanical Engineering (I2M)

Contactless manipulation of microparticles using acoustic waves holds promise for applications ranging from cell sorting to three-dimensional (3D) printing and tissue engineering. However, the unique potential of acoustic trapping to be applied in biomedical settings remains largely untapped. In particular, the main advantage of acoustic trapping o...

The ability to mechanically manipulate and control the spatial arrangement of biological materials is a critical capability in biomedicine and synthetic biology. Ultrasound has the ability to manipulate objects with high spatial and temporal precision via acoustic radiation force, but has not been used to directly control biomolecules or geneticall...

The ability to mechanically manipulate and control the spatial arrangement of biological materials is a critical capability in biomedicine and synthetic biology. Ultrasound has the ability to manipulate objects with high spatial and temporal precision via acoustic radiation force, but has not been used to directly control biomolecules or geneticall...

Biomedical microbubbles stabilized by a coating of magnetic or drug-containing nanoparticles show great potential for theranostics applications. Nanoparticle-coated microbubbles can be made to be stable, to be echogenic, and to release the cargo of drug-containing nanoparticles with an ultrasound trigger. This Article reviews the design principles...

In this work, the possibility of simultaneously trapping and rotating single polystyrene beads, or clusters, against gravity with an ultrasonic vortex beam is demonstrated. The induced rotation of a single particle is compared to a torque balance model accounting for the acoustic response of the particle. Two dominating dissipation mechanisms of th...

Micron-sized gas bubbles are notoriously difficult to isolate, handle and remotely control. Their large buoyancy in common liquids will usually force them to rise and burst at any gas/liquid interface or remain trapped against a solid boundary until dissolution. While bubble stability issues against dissolution have found numerous practical workaro...

The controlled rotation of solid particles trapped in a liquid by an ultrasonic vortex beam is observed. Single polystyrene beads, or clusters, can be trapped against gravity while simultaneously rotated. The induced rotation of a single particle is compared to a torque balance model accounting for the acoustic response of the particle. The measure...

Dexterous contactless manipulation of microscopic matter in three dimensions is possible since the development of optical tweezers. This scheme using a single laser beam can handle particles with forces in the piconewton range with subnanometer resolution. Although various acoustical traps, mainly using standing wave fields, have been proposed over...

Heterogeneity can be accounted for by a random potential in the wave equation. For acoustic waves in a fluid with fluctuations of both density and compressibility (as well as for electromagnetic waves in a medium with fluctuation of both permittivity and permeability) the random potential entails a scalar and an operator contribution. For simplicit...

Vortex beams are characterized by wavefronts twisting around their axis of propagation. A three dimensional region of silence tightly bounded by a high intensity ring emerges from the phase's screw dislocation, which can be used for particle manipulation. In this paper, we present the first experimental realization of selective 3D acoustical t...

We present theoretical calculations of the ensemble-averaged (or effective or coherent) wave field propagating in a heterogeneous medium considered as one realization of a random process. In the literature, it is usually assumed that heterogeneity can be accounted for by a random scalar function of the space coordinates, termed the potential. Physi...

As an acoustic wave impinges an obstacle, a mean force is exerted on its surface. This so-called radiation pressure arises from the non linear interaction between the wave and the object.The early history of this force did not suggest any application of such a feeble effect. Nevertheless, as technological advances improved the prospects of new powe...

We demonstrate the trapping of elastic particles by the large gradient force of a single acoustical beam in three dimensions. Acoustical tweezers can push, pull and accurately control both the position and the forces exerted on a unique particle. Forces in excess of 1 micronewton were exerted on polystyrene beads in the sub-millimeter range. A beam...

We present, in our knowledge, the first theoretical demonstration of the possibility to trap and manipulate particles in three dimensions with the radiation pressure exerted by a single acoustical beam. Numerical examples demonstrate that single-beam acoustical tweezers operating in three dimensions are feasible with a large variety of materials an...

Recent studies on the acoustic radiation forces exerted by sound impinging spherical objects suggest the use of structured wavefronts for particle entrapment and controlled manipulation. In the scope of understanding why it is made possible to trap and manipulate small particles with sound, we present a general model for the acoustic radiation forc...

This work aims to model the acoustic radiation forces acting on an elastic sphere placed in an inviscid fluid. An expression of the axial and transverse forces exerted on the sphere is derived. The analysis is based on the scattering of an arbitrary acoustic field expanded in the spherical coordinate system centered on the spherical scatterer. The...

A numerical method for the simulation of three-dimensional nonlinear acoustical wave propagation through a homogeneous or weakly heterogeneous medium is presented. This method is based on the resolution a nonlinear wave equation taking into account diffraction, nonlinearities and weak heterogeneities exact up to second order. It is numerically solv...

The numerical prediction of the wind noise in a car cabin requires distinguishing between the aerodynamic and the acoustic components of the wall pressure fluctuations loading the car side windows. It is theoretically possible to separate them using a time and space Fourier transform. Nevertheless the acoustic component is much smaller in amplitude...