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Published on: November 30, 2012
Shear surface waves in phononic crystals
1Université de Bordeaux, Institut de Mécanique et d'Ingénierie de Bordeaux, UMR 5295, Talence 33405, France. aak@nxt.ru
The Journal of the Acoustical Society of America
|February 1, 2013
Summary
This study theoretically confirms shear horizontal (SH) surface waves in 2D phononic crystals with asymmetric profiles. It establishes a link between bulk and surface wave speeds, offering a new calculation method.
Area of Science:
- Solid-state physics
- Acoustics
- Materials science
Background:
- Phononic crystals offer unique wave manipulation properties.
- Understanding surface waves is crucial for device applications.
- Asymmetric profiles introduce complex wave behaviors.
Purpose of the Study:
- To theoretically report the existence of shear horizontal (SH) surface waves.
- To demonstrate dispersion spectra with bandgaps for SH surface waves.
- To establish a link between effective speeds of SH bulk and surface waves.
Main Methods:
- Utilizing an integral projector method on evanescent modes.
- Avoiding explicit calculation of evanescent modes.
- Theoretical analysis of two-dimensional periodic phononic crystals.
Main Results:
- Existence of SH surface waves confirmed in asymmetric, depth-dependent phononic crystals.
- Demonstrated dispersion spectra showing bandgaps for subsonic and supersonic SH surface waves.
- Established a clear relationship between effective bulk and surface wave speeds.
Conclusions:
- The integral projector method provides an efficient way to study SH surface waves.
- The findings are applicable to designing phononic crystal devices.
- The method is extensible to vector waves and three-dimensional systems.
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