Research topics

Acoustic metamaterials and metasurfaces

Metaporous and metaporoelastic layers

These sound absorbing materials combine viscothermal losses arising from porous materials with periodic resonant elements. The role of the former is to attenuate sound, while the role of the latter is to trap the sound energy inside the structures at frequency much lower than the quarter-wavelength resonance one as well as to modify/tune the system attenuation. This results in perfect and broadband sound absoption for wavelength impiging the structure approximativeley 10 times larger than the structure thickness in reflection problems.

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Deep-subwavelength sound absorbers

Using the concept of strong dispersion subwavelength resonators are designed, which are then critically coupled to the exterior medium to design perfect sound absorbers for wavelength impiging the structure approximativeley 88 times larger than the structure thickness in reflection problems and 40 times larger than the structure thickness in transmission problems.

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Resonant sonic crystals

Resonant sonic crystals combines Bragg band gaps and resonant band gaps at much lower frequencies to design sound insulating structures.

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Porous and poroelastic metarials

Macroscopically inhomogeneous porous and poroelastic materials - graded porous and poroelastic materials

Macroscopically inhomogeneous porous and poroelastic materials are materials the macroscopic properties of which depend on the spatial coordinates. Graded porous and poroelastic materials can therefore be designed to impedance match the surrounding medium as well as attenuate much more the acoustic energy.

Inverse problems

Characterization of porous and poroelastic materials

Porous materials are characterized by means of ultrasonic and impedance tube measurements, notably via Bayesian approach. Poroelastic materials are characterized by means of Surface Acoustic Wave measurements.

Characterization of acoustic metamaterials

Acoustic metamaterials are characterized by means of square cross-sectional area impedance tube or fully anechoic chamber measurements.

Recovery of complex wavenumber/frequency dispersion relations

Complex wavenumber/frequency dispersion relations are recovered by means of the SLaTCoW method, which yields in the analysis of the spatial Laplace Transform of fields in the frequency domain.