Matthieu Guédra

We don’t have enough information about this author to calculate their statistics. If you think this is an error let us know.
Learn More
We report observations of strong nonlinear interactions between the spherical, translational, and shape oscillations of micrometer-size bubbles. This is achieved through high-speed recordings of single bubble dynamics driven by amplitude-modulated ultrasound. The features of mode coupling are highlighted through (i) the exponential growth of the(More)
Bubbles insonified by ultrasound can exhibit shape deformations and no more oscillate upon a purely spherical mode. Understanding and predicting the appearance of surface oscillations is essential for typical applications based on the acoustic response of bubbles (e.g. the use of contrast agents in echographic imaging), partly because shape modes can(More)
The subharmonic emission of sound coming from the nonlinear response of a bubble population is the most used indicator for stable cavitation. When driven at twice their resonance frequency, bubbles can exhibit subharmonic spherical oscillations if the acoustic pressure amplitude exceeds a threshold value. Although various theoretical derivations exist for(More)
An asymptotic method is applied to analyze the nonlinear oscillations of a gas bubble driven by a dual-frequency excitation. More specifically, the latter is considered as a combination of two neighboring, incommensurate frequencies and is treated as a nonstationary excitation. This implies that both amplitude and phase of the bubble response are slowly(More)
When exposed to sufficiently high ultrasound pressures, microbubbles can be generated spontaneously in tissue and undergo inertial cavitation where collapses result in physical effects. These effects range from petechial haemorrhage to complete cellular disruption, termed Histotripsy, depending on ultrasound parameters. This presentation will explore the(More)
  • 1