Scanning phononic lattices with surface acoustic waves
-
Robert E. Vines
Abstract
We have examined the propagation of surface acoustic waves across structures with periodically varying elastic properties. These so-called phononic lattices include a) alternating layers of aluminum and polymer in a multilayer structure, b) a 2-d hexagonal lattice of holes drilled in an aluminum substrate and filled with polymer, and c) a 2-d hexagonal array of Al posts surrounded by polymer. A simple method is employed for probing the elastic properties of these periodic structures with ultrasound in the 0.5–5 MHz range. Ultrasonic surface waves are introduced and detected by water-immersion transducers, cylindrically focused to a line on the sample surface. Transmission and reflection patterns are observed by continuously scanning the wavevector angle with respect to the symmetry axes of the lattice. By Fourier transforming the transmitted signals using a broadband source, we obtain the frequency responses of the lattices as a function of propagation angle. Phononic band gaps, waveguide channeling and Scholte-like interface modes are observed. The results are compared to models of the propagation of transverse waves through analogous bulk structures, for which theories are available. These preliminary models explain the basic features of the experimental results, such as frequency gaps and wave channeling. A number of observations, however, remain to be explained. The angle-scanning technique provides a powerful probe of these modulated structures.
© by Oldenbourg Wissenschaftsverlag, München
Articles in the same Issue
- Editorial: Phononic Crystals – Sonic Band-Gap Materials
- Classical wave localization and spectral gap materials
- Classical vibrational modes in phononic lattices: theory and experiment
- Scanning phononic lattices with surface acoustic waves
- Acoustic band gap measurements in waveguides with periodic resonant structures
- Experimental observation of resonant filtering in a two-dimensional phononic crystal waveguide
- Experimental study of guiding and filtering of acoustic waves in a two dimensional ultrasonic crystal
- Surface acoustic wave band gaps in micro-machined air/silicon phononic structures — theoretical calculation and experiment
- The layer multiple-scattering method applied to phononic crystals
- Tunneling and dispersion in 3D phononic crystals
- Transmission properties of locally resonant sonic materials with finite slab thickness
- Large enhancement of phononic gap in periodic and quasiperiodic elastic composites by using air inclusions
- Sound propagation in the time-domain by the Split-Operator technique
- Inverse design of phononic crystals by topology optimization
- Elastic waves in arrays of elliptic inclusions
- Books Received
Articles in the same Issue
- Editorial: Phononic Crystals – Sonic Band-Gap Materials
- Classical wave localization and spectral gap materials
- Classical vibrational modes in phononic lattices: theory and experiment
- Scanning phononic lattices with surface acoustic waves
- Acoustic band gap measurements in waveguides with periodic resonant structures
- Experimental observation of resonant filtering in a two-dimensional phononic crystal waveguide
- Experimental study of guiding and filtering of acoustic waves in a two dimensional ultrasonic crystal
- Surface acoustic wave band gaps in micro-machined air/silicon phononic structures — theoretical calculation and experiment
- The layer multiple-scattering method applied to phononic crystals
- Tunneling and dispersion in 3D phononic crystals
- Transmission properties of locally resonant sonic materials with finite slab thickness
- Large enhancement of phononic gap in periodic and quasiperiodic elastic composites by using air inclusions
- Sound propagation in the time-domain by the Split-Operator technique
- Inverse design of phononic crystals by topology optimization
- Elastic waves in arrays of elliptic inclusions
- Books Received
