Phononic crystals and manipulation of sound

Abstract

The acoustic properties of phononic crystals are presented, using numerical simulations. In a first part we study some possible applications of these composite materials. In particular, we show that defect modes (cavities, wave guides, stubs...) inserted inside the 2D periodic structure may lead to the possibility of manipulating the propagation of sound and realizing selective frequency filters and efficient devices for wavelength demultiplexing. We also report on the vibration modes of a 2D plate, i.e. a phononic crystal of finite thickness along the axis of the inclusions. We investigate the existence of absolute band gaps in the band structure of the plate, either free or deposited on a substrate. This should open new perspectives in the field of high‐frequency radiofrequency devices. Finally, we present the possibility of devicing sonic insulators for frequencies of the order of kHz with relatively small thicknesses of the phononic crystal sample as compared to the wavelength. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Shear Elastic Wave Refraction on a Gap between Piezoelectric Crystals with Uniform Relative Motion

“…The concept of acoustic tunneling is successfully applied now to interpretation of transfer effects of wave disturbances between phononic crystals (Qui et al, 2005;Van Der Biest et al, 2005;Pennec et al, 2009). Strictly speaking, there is not here the obvious analogy to acoustic tunneling of waves through a slot between piezoelectric crystals because of absence of a vacuum gap.…”

Phononic band gap and wave propagation on multiferroic-based acoustic metamaterials

“…Phononic crystals (PnCs) and acoustic metamaterials have generated rising scientific interests for very diverse technological applications ranging from sound abatement to ultrasonic imaging to telecommunications to thermal management and thermoelectricity [1]. PnCs and acoustic metamaterials are artificially structured composite materials that enable the manipulation of the dispersive properties of vibrational waves.…”

AVBVICVII ferroelectrics as novel materials for phononic crystals

“…Phononic crystals (PnCs) and acoustic metamaterials have generated rising scientific interests for very diverse technological applications ranging from sound abatement to ultrasonic imaging to telecommunications to thermal management and thermoelectricity [1]. In recent years great interest arises in the artificial periodic structures that can arise only in the human imagination.…”