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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Topological phononics arising from fluid-solid interactions.
Xiaoxiao Wu1,2, Haiyan Fan3, Tuo Liu4
1Faculties of Sciences and Engineering, The University of Hong Kong, Hong Kong, China.
Nature Communications
|October 17, 2022
Summary
Researchers explored topological phononics by combining fluid and solid acoustics. They realized type-II nodal rings and drumhead surface states in a 3D phononic crystal, paving the way for advanced acoustic devices.
Area of Science:
- Topological physics
- Classical acoustics
- Condensed matter physics
Background:
- Nontrivial band topologies are known in classical systems with device potential.
- Sound exhibits different dynamics in fluids (scalar) and solids (vector).
- Previous topological phononics research overlooked interactions between fluids and solids.
Purpose of the Study:
- To develop a novel approach for topological phononics using coupled fluid-solid interactions.
- To experimentally realize type-II nodal rings, which are elusive in phononics.
- To demonstrate hallmark phenomena like tilted drumhead surface states.
Main Methods:
- Design and fabrication of a three-dimensional phononic crystal.
- Utilizing the interplay between fluid and solid acoustic dynamics.
- Ultrasonic near-field scanning for experimental observation.
Main Results:
- Successful realization of type-II nodal rings in the phononic crystal.
- Direct observation of strongly tilted drumhead surface states.
- Demonstration of a new platform for topological phononics.
Conclusions:
- This work introduces a facile method for exploring topological physics in classical systems.
- The developed phononic approach enables the design of high-performance acoustic devices.
- Highlights the potential of hybrid fluid-solid systems for topological phenomena.
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