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Spatiotemporal Acoustic Vortex Beams with Transverse Orbital Angular Momentum
Hao Ge1, Shuai Liu1, Xiang-Yuan Xu1
1National Laboratory of Solid State Microstructures & Department of Materials Science and Engineering, Nanjing University, Nanjing, Jiangsu 210093, China.
Physical Review Letters
|July 21, 2023
Summary
Researchers generated Bessel-type spatiotemporal (ST) acoustic vortex beams, extending optical ST vortex beam applications to acoustics. This work demonstrates ST acoustic vortex beam generation and characterization, paving the way for new acoustic wave research.
Area of Science:
- Acoustics
- Wave Physics
- Optics
Background:
- Spatiotemporal (ST) vortex beams with transverse orbital angular momentum (OAM) have expanded research in optics.
- The application of ST vortex beams in other wave phenomena fields is of significant interest.
Purpose of the Study:
- To develop the spatiotemporal vortex concept in acoustics.
- To generate and characterize Bessel-type ST acoustic vortex beams.
- To explore the potential of acoustic systems for studying structured waves.
Main Methods:
- Generation of Bessel-type ST acoustic vortex beams.
- Characterization using scalar (pressure field) and vector (velocity field) approaches.
- Investigation of transverse spreading effects and mitigation using ellipse-shaped spectra.
- Experimental demonstration of orthogonality relations for different charges.
Main Results:
- Successful generation of Bessel-type ST acoustic vortex beams.
- Comprehensive characterization of acoustic vortex beam properties.
- Demonstration of reduced transverse spreading.
- Experimental validation of orthogonality for ST acoustic vortex beams.
Conclusions:
- The study successfully extends the ST vortex beam concept to acoustics.
- Acoustic systems offer a versatile platform for exploring spatiotemporally structured waves.
- This research inspires further investigation into exotic wave physics in acoustics.
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