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Title: Rainbow trapping of ultrasonic guided waves in chirped phononic crystal plates

Abstract

The rainbow trapping effect has been demonstrated in electromagnetic and acoustic waves. In this study, rainbow trapping of ultrasonic guided waves is achieved in chirped phononic crystal plates that spatially modulate the dispersion, group velocity, and stopband. The rainbow trapping is related to the progressively slowing group velocity, and the extremely low group velocity near the lower boundary of a stopband that gradually varies in chirped phononic crystal plates. As guided waves propagate along the phononic crystal plate, waves gradually slow down and finally stop forward propagating. The energy of guided waves is concentrated at the low velocity region near the stopband. Moreover, the guided wave energy of different frequencies is concentrated at different locations, which manifests as rainbow guided waves. We believe implementing the rainbow trapping will open new paradigms for guiding and focusing of guided waves. Furthermore, the rainbow guided waves with energy concentration and spatial separation of frequencies may have potential applications in nondestructive evaluation, spatial wave filtering, energy harvesting, and acoustofluidics.

Authors:
 [1];  [1]
  1. Univ. of South Carolina, Columbia, SC (United States)
Publication Date:
Research Org.:
Univ. of South Carolina, Columbia, SC (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
1346007
Grant/Contract Number:
NE0000726
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 7; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; acoustics; devices for energy harvesting; slow light

Citation Formats

Tian, Zhenhua, and Yu, Lingyu. Rainbow trapping of ultrasonic guided waves in chirped phononic crystal plates. United States: N. p., 2017. Web. doi:10.1038/srep40004.
Tian, Zhenhua, & Yu, Lingyu. Rainbow trapping of ultrasonic guided waves in chirped phononic crystal plates. United States. doi:10.1038/srep40004.
Tian, Zhenhua, and Yu, Lingyu. Thu . "Rainbow trapping of ultrasonic guided waves in chirped phononic crystal plates". United States. doi:10.1038/srep40004. https://www.osti.gov/servlets/purl/1346007.
@article{osti_1346007,
title = {Rainbow trapping of ultrasonic guided waves in chirped phononic crystal plates},
author = {Tian, Zhenhua and Yu, Lingyu},
abstractNote = {The rainbow trapping effect has been demonstrated in electromagnetic and acoustic waves. In this study, rainbow trapping of ultrasonic guided waves is achieved in chirped phononic crystal plates that spatially modulate the dispersion, group velocity, and stopband. The rainbow trapping is related to the progressively slowing group velocity, and the extremely low group velocity near the lower boundary of a stopband that gradually varies in chirped phononic crystal plates. As guided waves propagate along the phononic crystal plate, waves gradually slow down and finally stop forward propagating. The energy of guided waves is concentrated at the low velocity region near the stopband. Moreover, the guided wave energy of different frequencies is concentrated at different locations, which manifests as rainbow guided waves. We believe implementing the rainbow trapping will open new paradigms for guiding and focusing of guided waves. Furthermore, the rainbow guided waves with energy concentration and spatial separation of frequencies may have potential applications in nondestructive evaluation, spatial wave filtering, energy harvesting, and acoustofluidics.},
doi = {10.1038/srep40004},
journal = {Scientific Reports},
number = ,
volume = 7,
place = {United States},
year = {Thu Jan 05 00:00:00 EST 2017},
month = {Thu Jan 05 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 1work
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