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Updated: Jun 6, 2026
04:54
A Stable Phantom Material for Optical and Acoustic Imaging
Published on: June 16, 2023
Acoustic cloaking using layered pentamode materials
Clyde L Scandrett1, Jeffrey E Boisvert, Thomas R Howarth
1Department of Applied Mathematics, Naval Postgraduate School, Monterey, California 93943, USA.
The Journal of the Acoustical Society of America
|December 2, 2010
Summary
This study explores acoustic cloaks using metamaterials to minimize sound scattering from spheres. Researchers analyzed various cloak designs, considering material properties and operating frequencies for optimal performance.
Area of Science:
- Acoustics
- Metamaterials
- Wave Scattering
Background:
- Acoustic cloaking, though less studied than electromagnetic cloaking, is an area of theoretical interest.
- Metamaterials offer a pathway to achieving acoustic cloaking by manipulating sound waves.
- Previous work by Norris (2008) laid theoretical groundwork for cloaking devices.
Purpose of the Study:
- To extend theoretical analysis of acoustic cloaks based on coordinate transformations.
- To investigate a range of cloak designs, including those with isotropic and anisotropic material properties.
- To analyze the performance of these cloaks for plane wave scattering from a hard sphere.
Main Methods:
- Utilizing pentamode materials governed by a scalar acoustic equation for pseudopressure.
- Designing cloak material properties based on theoretical coordinate transformations to minimize scattered pressure.
- Exploring the parameter space, including material properties and operating frequency, for optimal cloak design.
Main Results:
- Analysis of cloaks with varying bulk moduli and density properties (isotropic/anisotropic).
- Demonstration of cloaks composed of fluid/pentamode layers.
- Initial exploration of parameter space for optimizing acoustic cloak design against a hard sphere.
Conclusions:
- The study provides a theoretical framework for designing acoustic cloaks using metamaterials.
- It highlights the importance of material properties and operating frequency in achieving effective cloaking.
- Further exploration of parameter space is needed for optimal acoustic cloak design.
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