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Updated: May 30, 2026
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
Acoustic metamaterial with negative modulus
Sam Hyeon Lee1, Choon Mahn Park, Yong Mun Seo
1Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749, Korea.
Summary
This study introduces an acoustic metamaterial with a negative effective modulus below 450 Hz. This novel material effectively blocks low-frequency sound waves, offering new possibilities for acoustic control.
Area of Science:
- Acoustics
- Materials Science
- Physics
Background:
- Acoustic metamaterials offer unique wave manipulation properties.
- Controlling sound propagation at low frequencies remains a significant challenge.
Purpose of the Study:
- To experimentally and theoretically investigate an acoustic metamaterial.
- To demonstrate negative effective modulus in a specific frequency range.
- To explain the observed acoustic behavior through theoretical modeling.
Main Methods:
- Fabrication of a one-dimensional acoustic metamaterial with an array of side holes on a tube.
- Experimental measurement of acoustic wave propagation.
- Theoretical analysis of the metamaterial's frequency characteristics.
Main Results:
- The acoustic metamaterial exhibited a negative effective modulus from 0 to 450 Hz.
- Acoustic waves above 450 Hz propagated well through the structure.
- Sound transmission was effectively blocked below 450 Hz.
Conclusions:
- The fabricated acoustic metamaterial successfully demonstrated tunable sound blocking below 450 Hz.
- The observed frequency characteristics are analogous to plasma oscillations in metals.
- The study provides a theoretical framework explaining the experimental findings.
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