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Updated: Mar 17, 2026
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
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A tunable acoustic metamaterial with double-negativity driven by electromagnets
Zhe Chen1, Cheng Xue1, Li Fan1
1Lab of Modern Acoustics, Institute of Acoustics, Nanjing University, Nanjing, 210093, P. R. China.
Scientific Reports
|July 23, 2016
Summary
This study introduces a tunable acoustic metamaterial with adjustable frequency bands using a direct-current voltage. A low voltage (6V) significantly shifts the double-negativity pass band by 40%, offering easy control and minimal electromagnetic interference.
Area of Science:
- Acoustics
- Materials Science
- Condensed Matter Physics
Background:
- Passive acoustic metamaterials face limitations in frequency tunability.
- Actively tunable metamaterials are crucial for advanced acoustic applications.
Purpose of the Study:
- To present a novel tunable acoustic metamaterial with double-negativity.
- To demonstrate voltage-controlled adjustment of its characteristic frequency bands.
Main Methods:
- The metamaterial design utilizes periodical membranes and side holes.
- Electromagnets apply stresses to tune membrane tension and stiffness.
- External direct-current voltage controls the electromagnets.
Main Results:
- The double-negativity pass band is effectively controlled by external voltage.
- A 6V direct-current voltage shifts the pass band by 40% bandwidth.
- The metamaterial exhibits marginal electromagnetic interference.
Conclusions:
- The developed acoustic metamaterial is easily controlled and highly tunable.
- It offers a promising solution for dynamic acoustic wave manipulation.
- The design minimizes electromagnetic interference, enhancing practical applicability.
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