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Updated: Feb 14, 2026

Optimization of Crystal Growth for Neutron Macromolecular Crystallography
Published on: March 13, 2021
Systematic Design of Phononic Band Gap Crystals for Elastic Waves at the Specified Target Frequency via Topology
Jingjie He1, Zhiyuan Jia2, Yuhao Bao2
1Marine Engineering College, Dalian Maritime University, Dalian 116026, China.
Abstract:
Phononic band gap crystals are characterized by periodic scatterers embedded within a matrix, which enable precise modulation of acoustic or elastic waves. Conventional optimization prioritizes bandwidth maximization, yet practical engineering often requires band gaps at specified frequencies. This requirement creates a significant design challenge. To this end, we develop a topology optimization strategy capable of maximizing elastic wave band gaps around prescribed target frequencies. The approach utilizes Material-Field Series Expansion (MFSE) for unit cell representation and a gradient-free Kriging-based algorithm to tackle the complex optimization problems. This strategy is systematically applied to optimize the band gaps of out-of-plane, in-plane, and complete wave modes, and is further extended to more complex scenarios involving dual-target frequencies. A variety of numerical results demonstrate the method's effectiveness in engineering phononic crystals for bespoke frequency specifications.
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