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Updated: Aug 23, 2025
06:51
Microparticle Manipulation by Standing Surface Acoustic Waves with Dual-frequency Excitations
Published on: August 21, 2018
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Shaping contactless radiation forces through anomalous acoustic scattering
Matthew Stein1, Sam Keller1, Yujie Luo1
1Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, 55455, USA.
Nature Communications
|November 2, 2022
Summary
Researchers have broken traditional limits in contactless manipulation using acoustic waves and metasurfaces. This breakthrough enables new forms of acoustic actuation, including self-guidance and tractor beaming, independent of object size and shape.
Area of Science:
- Acoustics
- Metamaterials
- Wave physics
Background:
- Waves transfer momentum and exert force, enabling contactless manipulation.
- Conventional wave scattering limits manipulation force based on object geometry.
Purpose of the Study:
- To overcome intrinsic limitations in wave-based contactless manipulation.
- To demonstrate novel acoustic actuation using metasurfaces.
Main Methods:
- Utilizing subwavelength-structured surfaces (metasurfaces) with acoustic waves.
- Investigating anomalous scattering phenomena for force control.
Main Results:
- Demonstrated acoustic force control independent of object shape and size.
- Achieved self-guidance of metasurface objects by acoustic waves.
- Exhibited tractor beaming, pulling metasurface objects with acoustic waves.
Conclusions:
- Metasurface physics unlocks new frontiers in acoustic contactless actuation.
- Novel actuation mechanisms beyond traditional wave-matter interactions are enabled.
- Control over surface features allows unprecedented manipulation capabilities.
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