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Abstract Metasurfaces open up unprecedented potential for wave engineering using subwavelength sheets. However, a severe limitation of current acoustic metasurfaces is their poor reconfigurability to achieve distinct functions on demand. Here a programmable acoustic metasurface that contains an array of tunable subwavelength unit cells to break the limitation and realize versatile two‐dimensional wave manipulation functions is reported. Each unit cell of the metasurface is composed of a straight channel and five shunted Helmholtz resonators, whose effective mass can be tuned by a robust fluidic system. The phase and amplitude of acoustic waves transmitting through each unit cell can be modulated dynamically and continuously. Based on such mechanism, the metasurface is able to achieve versatile wave manipulation functions, by engineering the phase and amplitude of transmission waves in the subwavelength scale. Through acoustic field scanning experiments, multiple wave manipulation functions, including steering acoustic waves, engineering acoustic beams, and switching on/off acoustic energy flow by using one design of metasurface are visually demonstrated. This work extends the metasurface research and holds great potential for a wide range of applications including acoustic imaging, communication, levitation, and tweezers.
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Versatile Standing Wave Generation Between Arbitrarily Oriented Surfaces Using Acoustic Metasurface Deflectors and Retroreflectors
Acoustic wave devices using standing wave configurations have gained interest in various fields like healthcare diagnostics and manufacturing. Their functionalities span from cell sorting to microscale fiber assembly through periodic acoustic pressure fields. Conventional methods usually require parallel acoustic emitters and reflective surfaces, producing constrained standing wave patterns. In this paper, an effective approach for creating versatile acoustic standing wave fields using an acoustic metasurface deflector and retroreflector is introduced. The deflector manipulates the direction of incoming acoustic waves coupled with the retroreflector to reflect these waves back to the source. The proposed design allows the creation of standing waves that are not constrained by the relative angles of the two surfaces involved and allows for customizable wave patterns beyond the standard limits with enhanced adaptability. The system's effectiveness is evaluated through computational simulations using finite element analysis and experimental validation based on a 3D‐printed prototype. Results suggest that versatile standing waves between arbitrarily oriented surfaces can be produced through the careful design of the metasurface deflector and retroreflector. This approach can improve the performance of standing wave applications in particle manipulation, thus broadening the range of practical implementations for ultrasound and acoustofluidic technologies.
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- PAR ID:
- 10548731
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Intelligent Systems
- Volume:
- 7
- Issue:
- 3
- ISSN:
- 2640-4567
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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