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arXiv · 1111.1457

Ultrawide phononic band gap for combined in-plane and out-of-plane waves

Osama R. Bilal·Mahmoud I. Hussein
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Abstract

We consider two-dimensional phononic crystals formed from silicon and voids, and present optimized unit cell designs for (1) out-of-plane, (2) in-plane and (3) combined out-of-plane and in-plane elastic wave propagation. To feasibly search through an excessively large design space (10e40 possible realizations) we develop a specialized genetic algorithm and utilize it in conjunction with the reduced Bloch mode expansion method for fast band structure calculations. Focusing on high symmetry plain-strain square lattices, we report unit cell designs exhibiting record values of normalized band-gap size for all three categories. For the combined polarizations case, we reveal a design with a normalized band-gap size exceeding 60%.

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Osama R. Bilal, Mahmoud I. Hussein. 2011-11-06. Ultrawide phononic band gap for combined in-plane and out-of-plane waves. https://doi.org/10.1103/physreve.84.065701

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