Groupement De Recherche Européen : GDRE-US

Phononic crystals and metamaterials have attracted a growing interest during the last decade, because of their remarkable properties : pass bands, forbidden bands, negative refraction properties, phenomena related to local resonances, allowing various applications : simple or complex filtering, inversed Doppler effect, focalisation, as well as cloaking. Nevertheless, a major point is the knowledge of the effective properties of these materials, in order to help designing devices and broadening theirs capabilities.

The goal of this workshop is, beyond the presentation of research activities on phononic crystals and metamaterials, to give a state of art on this topic, and particularly : ➢ The existing homogenisation techniques : tools, hypothesis, validity domain, materials (fluid, solid…), 1D or 2D or 3D dimensional geometries, periodic or disordered structures, ➢ Phenomena and some problems, the limits of the models (interfaces, mathematical problems…), ➢ Some examples of applications of phononic crystals and metamaterials for which knowing the effective properties is of importance, in order to help in their design.

Program

Periodic structures

• A. N. Norris, A. L. Shuvalov, A. A. Kutsenko : Dynamic effective medium theory for periodic media

• A. Kutsenko, A. L. Shuvalov, A. N. Norris, O. Poncelet : Effective speed of elastic waves in phononic crystals

• S. Fliss : On the relevance of effective models of metamaterials near the boundary

• J. P. Groby, V. Tournat, O. Umnova, V. Romero Garcia : Overcoming the homogenization limit for the effective properties of finite-depth sonic crystals

• M. Dubois, M. Farhat, E. Bossy, S. Enoch, S. Guenneau, P. Sebbah : Flat lens for time-domain Lamb waves focusing

• A. C. Hladky-Hennion, J. Vasseur, B. Dubus, C. Croenne, A. Norris : Recent results on the negative refraction of longitudinal waves and related questions

• Y. Achaoui, V. Laude, S. Benchabane, A. Khelif : Dispersion of surface acoustic waves and LSAWs in phononic crystals of pillars

• A. J. Mulholland : Mathematical modelling of piezoelectric periodic materials used in the design of ultrasonic transducers

Disordered structure

• V. Pagneux, A. Maurel, P.A. Martin : Propagation in 1D system with disorder. Finite size effect for the effective properties of a periodic structure with disorder

• A. Maurel, O. Richoux, P. Martin, V. Pagneux : Effective transmission of a perturbed periodic 1D system

• T. Brunet, C. Aristégui, O. Poncelet : Design of locally resonant metafluids.