Wavefront modulation and subwavelength diffractive acoustics with an acoustic metasurface

Area of Science:

• Acoustics
• Materials Science
• Wave Physics

Background:

• Metasurfaces offer advanced wavefront-shaping capabilities with planar profiles.
• Acoustic metasurfaces are highly sought after for enhancing acoustic applications but face design challenges.

Purpose of the Study:

• To design and realize a novel acoustic metasurface with enhanced wave manipulation properties.
• To overcome limitations of traditional metamaterial design for acoustic applications.

Main Methods:

• Utilized tapered labyrinthine metamaterials for acoustic metasurface construction.
• Demonstrated beam steering based on the generalized Snell's law.
• Investigated unique properties like wave mode conversion and higher-order diffraction.

Main Results:

• The acoustic metasurface successfully steered acoustic beams as predicted.
• Observed conversion of propagating waves to surface modes.
• Exhibited extraordinary beam-steering and apparent negative refraction via higher-order diffraction.

Conclusions:

• The developed acoustic metasurface offers a new design paradigm for acoustic signal modulation.
• Potential applications include acoustic imaging, beam steering, and ultrasound lens design.