Bilal Osama R, Hussein Mahmoud I
Department of Aerospace Engineering Sciences, University of Colorado Boulder, Colorado 80309, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Dec;84(6 Pt 2):065701. doi: 10.1103/PhysRevE.84.065701. Epub 2011 Dec 20.
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 (~10(40) 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 case of combined polarizations, we reveal a design with a normalized band-gap size exceeding 60%.
我们考虑由硅和空洞构成的二维声子晶体，并针对（1）面外、（2）面内以及（3）面外与面内弹性波传播的组合情况，给出优化的晶胞设计。为了在过大的设计空间（约10^40种可能的实现方式）中进行可行的搜索，我们开发了一种专门的遗传算法，并将其与简化的布洛赫模式展开方法结合使用，以进行快速的能带结构计算。聚焦于高对称平面应变方形晶格，我们报告了在所有这三类情况中展现出归一化带隙尺寸创纪录值的晶胞设计。对于组合极化的情况，我们揭示了一种归一化带隙尺寸超过60%的设计。
