Chaotic Wave Scattering in Open Systems - from elastic waves to reverberation chambers

International audienceAny measurement opens a wave system. This coupling to the continuum drastically changes the system properties by converting discrete modes into decaying resonance states and induces currents that did not exist in the closed system. One possible description is the effective Hamiltonian formalism. As a consequence, typical quantities investigated in the realm of Wave chaos have to be modified like nearest neighbor spacing distributions, avoided crossings, and new features occur like resonance widths. We will be interested in their statistical properties in the case of chaotic systems and mainly concerned with experimental investigations of those properties using classical waves like microwaves or elastic waves. In particular, we will present results on wave functions and measures of openness through a non-orthogonality parameter. Finally, we will show how a simple modification of the shape of a reverberation chamber consisting in inserting a metallic hemisphere on a cavity wall may improve the required homogeneity and isotropy of the field for EMC tests. This contribution is joint work with Fabrice Mortessagne (LPMC, University of Nice, France), Dima Savin (Brunel, UK), Charles Poli (Cuernavaca, Mexico), Elodie Richalot (EESYCOM, UMLV, France), Kamardine Selemani (ESYCOM, UMLV, France) and Jean-Baptiste Gros (LPMC, University of Nice, France)