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Updated: Mar 31, 2026
11:08
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
19.6K
Sharp bends of phononic crystal surface modes
Ahmet Cicek1, Aysevil Salman, Olgun Adem Kaya
1Department of Physics, Faculty of Arts and Science, Mehmet Akif Ersoy University, 15030 Burdur, Turkey. Department of Electrical Engineering, Jack Baskin School of Engineering, University of California Santa Cruz, 1156 High Street, CA 95064, USA.
Summary
This study enhances surface wave bending in phononic crystals (PnCs) using optimized scatterers, boosting transmittance from 5% to 75%. Optimized PnC sharp bends show potential for acoustic ring resonators.
Area of Science:
- Acoustics
- Materials Science
- Condensed Matter Physics
Background:
- Surface waves in two-dimensional phononic crystals (PnCs) are crucial for wave manipulation.
- Sharp bends in PnCs typically suffer from low surface wave transmittance.
- Controlling wave propagation at interfaces requires precise structural design.
Purpose of the Study:
- To numerically demonstrate sharp bending of surface waves at a 2D PnC interface.
- To optimize the design of a diagonally offset cylindrical scatterer for enhanced wave transmittance.
- To explore the application of optimized PnC sharp bends as acoustic ring resonators.
Main Methods:
- Finite-element method (FEM) simulations were employed to model wave propagation.
- A genetic algorithm was used to optimize structural parameters for sharp bends.
- Key parameters included scatterer radius, PnC corner cylinder radius, and their separation distance.
Main Results:
- Surface wave transmittance was significantly enhanced from 5% to approximately 75% after optimization.
- Optimized sharp bends exhibited a series of transmittance peaks with exponentially increasing maxima and decreasing widths at higher frequencies.
- Optimal parameters involved a specific diagonally offset scatterer size and proximity to the PnC.
Conclusions:
- The study successfully demonstrates enhanced surface wave bending in PnCs through optimized scatterer design.
- The optimized structures show potential for use as efficient acoustic ring resonators.
- Precise control over phononic crystal geometry is key to achieving high transmittance for sharp bends.
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