Enhanced sensing and conversion of ultrasonic Rayleigh waves by elastic metasurfaces

Colombi, Andrea and Ageeva, Victoria and Smith, Richard J. and Clare, Adam T. and Patel, Rikesh and Clark, Matt and Colquitt, Daniel and Roux, Philippe and Guenneau, Sebastien and Craster, Richard V. (2017) Enhanced sensing and conversion of ultrasonic Rayleigh waves by elastic metasurfaces. Scientific Reports, 7 . 6750/1-6750/9. ISSN 2045-2322

[img]
Preview
PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Available under Licence Creative Commons Attribution.
Download (2MB) | Preview

Abstract

Recent years have heralded the introduction of metasurfaces that advantageously combine the vision of sub-wavelength wave manipulation, with the design, fabrication and size advantages associated with surface excitation. An important topic within metasurfaces is the tailored rainbow trapping and selective spatial frequency separation of electromagnetic and acoustic waves using graded metasurfaces. This frequency dependent trapping and spatial frequency segregation has implications for energy concentrators and associated energy harvesting, sensing and wave filtering techniques. Different demonstrations of acoustic and electromagnetic rainbow devices have been performed, however not for deep elastic substrates that support both shear and compressional waves, together with surface Rayleigh waves; these allow not only for Rayleigh wave rainbow effects to exist but also for mode conversion from surface into shear waves. Here we demonstrate experimentally not only elastic Rayleigh wave rainbow trapping, by taking advantage of a stop-band for surface waves, but also selective mode conversion of surface Rayleigh waves to shear waves. These experiments performed at ultrasonic frequencies, in the range of 400–600 kHz, are complemented by time domain numerical simulations. The metasurfaces we design are not limited to guided ultrasonic waves and are a general phenomenon in elastic waves that can be translated across scales.

Item Type: Article
Schools/Departments: University of Nottingham, UK > Faculty of Engineering
Identification Number: 10.1038/s41598-017-07151-6
Depositing User: Eprints, Support
Date Deposited: 16 Aug 2017 08:42
Last Modified: 17 Aug 2017 10:49
URI: http://eprints.nottingham.ac.uk/id/eprint/44925

Actions (Archive Staff Only)

Edit View Edit View