Bilayer synergetic coupling double negative acoustic metasurface and cloak

Area of Science:

• Acoustics
• Metamaterials
• Wave Physics

Background:

• Metasurfaces offer unique acoustic manipulation capabilities.
• Designing structures with double negative properties is crucial for advanced acoustic control.
• Achieving broadband sound absorption and full phase shift control remains a challenge.

Purpose of the Study:

• To propose a novel bilayer plate-type metasurface.
• To achieve perfect absorption and double negative acoustic parameters.
• To demonstrate versatile phase manipulation for acoustic cloaking and dark skin applications.

Main Methods:

• Utilizing a synergetic coupling design concept between resonant and anti-resonant plates.
• Constructing a bilayer unit for pre-defined functional components.
• Analyzing the simultaneous negative effective mass density and bulk modulus.

Main Results:

• Realization of perfect absorption and double negative bands.
• Achieved continuous phase shifts covering a full 2π range.
• Demonstrated a 2D omnidirectional broadband acoustical dark skin (800-6000 Hz).

Conclusions:

• The proposed bilayer metasurface enables simultaneous perfect absorption and double negative properties.
• The design facilitates the creation of 3D acoustic cloaks and 2D acoustical dark skins.
• This work holds potential for applications in sound attenuation, filtering, superlens, imaging, and wave steering.