Gradient index phononic crystals and metamaterials

Abstract

Phononic crystals and acoustic metamaterials are periodic structures whose effective properties can be tailored at will to achieve extreme control on wave propagation. Their refractive index is obtained from the homogenization of the infinite periodic system, but it is possible to locally change the properties of a finite crystal in such a way that it results in an effective gradient of the refractive index (GRIN). In such case the propagation of waves can be accurately described by means of ray theory, and different refractive devices can be designed in the framework of wave propagation in inhomogeneous media. In this paper we review the different devices that have been studied for the control of both bulk or guided acoustic waves based on graded phononic crystals.

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Cited by in corpus (15)

• Ultrasound Beam Steering with Flattened Acoustic Metamaterial Luneburg Lens
• Gradient zigzag metamaterial beams as broadband vibration isolators for beam-like structures
• Experimental realization of negative refraction and subwavelength imaging for flexural waves in phononic crystal plates
• Piezoelectric metastructures for simultaneous broadband energy harvesting and vibration suppression of traveling waves
• Existence of Corner Modes in Elastic Twisted Kagome Lattices
• Metaclusters for the Full Control of Mechanical Waves
• Broadband Acoustic Collimation and Focusing using Reduced Aberration Acoustic Luneburg Lens
• Gradient-index nanophotonics
• Non-singular and singular flat bands in tunable acoustic metamaterials
• Analytical Modeling of Acoustic Exponential Materials and Physical Mechanism of Broadband Anti-Reflection
• Inverse Design of Thin-Plate Elastic Wave Devices
• Grayscale control of local magnetic properties with direct-write laser annealing
• Edge modes for flexural waves in quasi-periodic linear arrays of scatterers
• Graded phononic metamaterials: Scalable design meets scalable microfabrication
• Acoustic jet based on acoustic metamaterial