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Sound non-reciprocity based on synthetic magnetism
Zhaoxian Chen1, Zhengwei Li2, Jingkai Weng2
1Collaborative Innovation Center of Advanced Microstructures, Key Laboratory of Modern Acoustics of Ministry of Education, Institute of Acoustics, Department of Physics, Nanjing University, Nanjing 210093, China; College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China.
Science Bulletin
|August 21, 2023
Summary
Researchers created a novel non-reciprocal acoustic system using synthetic magnetism. This system enables efficient, unidirectional sound transport with high isolation, paving the way for advanced acoustic devices.
Area of Science:
- Acoustics
- Condensed Matter Physics
- Metamaterials
Background:
- Synthetic magnetism has been achieved for photons and phonons using spatiotemporal modulation.
- Non-reciprocity is crucial for developing advanced wave manipulation devices.
Purpose of the Study:
- To design and demonstrate a non-reciprocal acoustic system.
- To achieve efficient, unidirectional acoustic transport with high isolation.
Main Methods:
- Utilizing a three-cavity system with dynamic and static couplings.
- Inducing synthetic magnetic flux via phase-correlated modulations.
- Applying the rotating wave approximation to control transport properties.
Main Results:
- Demonstrated frequency-preserved unidirectional acoustic transport.
- Achieved a 45-dB isolation ratio.
- Obtained a 0.85 forward transmission.
Conclusions:
- The study successfully realized a highly efficient non-reciprocal acoustic system.
- Results offer a pathway towards acoustic non-reciprocal technologies and Floquet topological insulators for sound.
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