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Updated: May 30, 2026
04:54
A Stable Phantom Material for Optical and Acoustic Imaging
Published on: June 16, 2023
Experimental acoustic ground cloak in air
Bogdan-Ioan Popa1, Lucian Zigoneanu, Steven A Cummer
1Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, USA. bap7@ee.duke.edu
Physical Review Letters
|July 21, 2011
Summary
Researchers developed a compact, broadband acoustic cloak using perforated plastic plates. This transformation acoustics device effectively manipulates sound in air, demonstrating practical applications for acoustic cloaking technology.
Area of Science:
- Acoustics
- Materials Science
- Metamaterials
Background:
- Acoustic cloaking aims to control sound wave propagation.
- Transformation acoustics provides a theoretical framework for designing cloaking devices.
- Previous acoustic cloaks often faced limitations in bandwidth, size, or material complexity.
Purpose of the Study:
- To design, fabricate, and analyze a class of two-dimensional acoustic cloaking coatings in air.
- To demonstrate the feasibility of using metamaterials for practical acoustic cloaking.
- To achieve homogeneous, broadband, and compact cloaking shells.
Main Methods:
- Utilized transformation acoustics principles with linear coordinate transformations.
- Designed metamaterials from perforated plastic plates to achieve required anisotropic material parameters.
- Assessed cloak performance by measuring the sound field around the device using a broadband source.
Main Results:
- Successfully designed and fabricated a compact, broadband acoustic cloak.
- Demonstrated that highly anisotropic material parameters are achievable in metamaterials.
- Experimental measurements confirmed effective manipulation of sound waves around the cloak.
Conclusions:
- The developed acoustic cloak is effective and practical for manipulating sound in air.
- Metamaterials made of perforated plastic plates offer a low-complexity solution for acoustic cloaking.
- This work validates the application of transformation acoustics in realizing functional acoustic devices.
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