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Refraction/reflection reversal in two-dimensional acoustic metagratingsa)
Hong-Yu Zou1, Jiao Qian1, Jianping Xia1
1Research Center of Fluid Machinery Engineering and Technology, School of Physics and Electronic Engineering, Jiangsu University, Zhenjiang 212013, China.
The Journal of the Acoustical Society of America
|September 23, 2024
Summary
Acoustic metagratings (AMs) extend the generalized Snell
Area of Science:
- Acoustics
- Metamaterials
- Wave physics
Background:
- Acoustic metasurfaces primarily use phase gradients for wave manipulation.
- Acoustic metagratings (AMs) combine phase gradients and diffraction for extended generalized Snell's law (GSL) capabilities.
- Previous research on AMs has been limited to 1D periodic structures and 3D space applications.
Purpose of the Study:
- To investigate the extension of GSL in 3D space using 2D periodic acoustic metagratings.
- To experimentally demonstrate functional 2D AMs for arbitrary sound refraction and reflection control in 3D.
- To develop dual-layer sound lenses with switchable refraction/reflection properties.
Main Methods:
- Design and fabrication of 2D periodic acoustic metagratings.
- Experimental validation of AM performance under various 3D incidence angles.
- Construction and testing of dual-layer sound lenses utilizing AMs.
Main Results:
- Demonstrated 2D AMs capable of sound refraction and reflection at any 3D incidence angle.
- Achieved reversal of refraction and reflection by adjusting incident angles.
- Successfully created dual-layer sound lenses with tunable acoustic properties via AM assembly.
Conclusions:
- The study extends AM capabilities to complex 3D wavefront manipulation.
- The developed AMs offer versatile control over sound propagation in three dimensions.
- This work holds potential for advanced acoustic device applications.
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