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Microparticle Manipulation by Standing Surface Acoustic Waves with Dual-frequency Excitations
Published on: August 21, 2018
Manipulating acoustic wavefront by inhomogeneous impedance and steerable extraordinary reflection
Jiajun Zhao1, Baowen Li, Zhining Chen
11] Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576, Republic of Singapore [2] Department of Physics and Centre for Computational Science and Engineering, National University of Singapore, Singapore 117546, Republic of Singapore and.
Scientific Reports
|August 30, 2013
Summary
This study introduces an impedance-governed generalized Snell's law of reflection (IGSL) for acoustic wavefront manipulation. The novel method allows for controlled acoustic reflections, enabling new applications in acoustics.
Area of Science:
- Acoustics
- Wave Phenomena
- Materials Science
Background:
- Acoustic wavefront manipulation is crucial for diverse applications.
- Existing methods often rely on Fermat's principle, limiting control.
- Novel approaches are needed for precise steering of acoustic reflections.
Purpose of the Study:
- To establish a connection between acoustic surface impedance and reflected wavefronts.
- To introduce a new principle for acoustic reflection control.
- To enable novel applications in the acoustic community.
Main Methods:
- Development of the impedance-governed generalized Snell's law of reflection (IGSL).
- Utilizing Green's function and integral equations for theoretical formulation.
- Designing a flat surface with tunable acoustic impedance using Helmholtz resonators.
Main Results:
- Demonstration of double reflections: ordinary and extraordinary.
- Extraordinary reflection allows for unprecedented acoustic wavefront manipulation.
- Ordinary reflection can be controllably switched on or off via impedance adjustment.
Conclusions:
- The proposed IGSL provides a powerful tool for acoustic wavefront engineering.
- Tunable acoustic impedance surfaces offer versatile control over reflections.
- This research opens avenues for advanced acoustic devices and applications.
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