报 告 人:  Nesrine Kherraz

报告时间:  2017-05-27上午10:00-11:30

报告地点:  机械工程楼Z307

Abstract

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 S0 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.

CV

Nesrine Kherraz graduated in Acoustics and Fluids with specialization in "Sensors and NDT by ultrasounds" at the Denis Diderot University of Paris in 2013. In 2017 she discussed her PhD thesis in Physical Acoustics, entitled "Development of active phononic crystals and metamaterials for ultrasound applications" defended at the François Rabelais University of Tours, in co-direction with the Laboratory GREMAN (research group in materials, microelectronics, acoustics and nanotechnologies) of Blois and the laboratory of waves and complex media of Le Havre. Her supervisors have been: Profs. Franck Levassort, Bruno Morvan and Lionel Haumesser. During her thesis, she developed both numerical and experimental skills for the comprehension of wave propagation issues in piezoelectric phononic plates.
Now she is at the "Laboratory of Waves and Complex Media" (CNRS UMR 6294) of Le Havre as Temporary research and teaching assistant (ATER) at the Department of electrical, industrial and computing engineering (GEII) - IUT of Le Havre - Le Havre Normandy University, Le Havre.

发布人：王艳锋（力学系）