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Acoustic frequency filter based on anisotropic topological phononic crystals
Ze-Guo Chen1, Jiajun Zhao1,2, Jun Mei3
1King Abdullah University of Science and Technology (KAUST),Division of Computer, Electrical and Mathematical Science and Engineering (CEMSE), Thuwal, 23955-6900, Saudi Arabia.
Scientific Reports
|November 10, 2017
Summary
We designed an acoustic frequency filter using a 2D anisotropic phononic crystal. This design enables tunable wave propagation control for advanced acoustic filtering applications.
Area of Science:
- Acoustics
- Condensed Matter Physics
- Materials Science
Background:
- Phononic crystals offer unique wave manipulation properties.
- Anisotropy in phononic crystals can lead to directional bandgaps.
- Topological bandgaps provide novel wave transport phenomena.
Purpose of the Study:
- To design and analyze an acoustic frequency filter.
- To explore wave propagation control using 2D anisotropic phononic crystals.
- To investigate the impact of broken time-reversal symmetry on bandgap properties.
Main Methods:
- Design of a two-dimensional anisotropic phononic crystal.
- Analysis of anisotropic band structure and bandgaps.
- Development of a tight-binding model for effective Hamiltonian characterization.
Main Results:
- Anisotropic band structure exhibits directional or combined bandgaps.
- Broken time-reversal symmetry induces a topologically nontrivial bandgap.
- The system demonstrates tunable anisotropic wave propagation and filtering.
Conclusions:
- The proposed phononic crystal design enables effective acoustic frequency filtering.
- Anisotropy plays a crucial role in achieving directional and tunable wave propagation.
- The tight-binding model accurately captures the system's behavior and anisotropic effects.
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