Controlling Bragg gaps induced by electric boundary conditions in phononic piezoelectric plates
Résumé
A Phononic Crystal (PC), constituted of a homogeneous piezoelectric plate covered by a 1D
periodic arrangement of thin metallic electrodes on both surfaces, is studied. The application of
Electric Boundary Conditions (EBCs) on the electrodes enables the propagation control of the
ultrasonic guided waves in the PC. The band structure is investigated for different EBCs: the
electrodes are either at a floating potential or they are alternately short-circuited and at a floating
potential. In the latter case, a Bragg gap appears for the fundamental S$_0$ guided Lamb mode. These
results are verified experimentally and compared to finite element calculations. A physical interpretation
is also given, relying on the symmetry of the electric potential fields associated with these
guided modes
Origine | Fichiers éditeurs autorisés sur une archive ouverte |
---|