Hong Sungyeon, Nerse Can, Oberst Sebastian, Saadatfar Mohammad
School of Cybernetics, College of Engineering, Computing and Cybernetics, The Australian National University, Canberra, ACT 2601, Australia.
Centre for Audio, Acoustics and Vibration, Faculty of Engineering and IT, University of Technology Sydney, Sydney, NSW 2040, Australia.
PNAS Nexus. 2024 Nov 14;3(12):pgae510. doi: 10.1093/pnasnexus/pgae510. eCollection 2024 Dec.
Disordered hyperuniform materials are increasingly drawing attention due to their unique physical properties, associated with global isotropy and locally broken orientational symmetry, that set them apart from traditional crystalline materials. Using a dynamic space-partitioning process, we generate disordered hyperuniform cellular structures where distinct patterns of pentagonal and heptagonal topological defects emerge within hexagonal domains. The microscopic defect dynamics are guided by local topological transitions, commonly observed in viscoelastic systems. This leads to a reduction in the system's structural entropy as hyperuniformity is attained, marked by the rise and fall of certain locally favored motifs. Further, we introduce an elastic hyperuniform material that exhibits evolving topological mechanical states in the continuum. Through vibration experiments and numerical analysis, we show energy localization around these defects, which is tied to the topological band gaps inherent to our geometry-driven material. We suggest that this robust dynamic mechanism influences a broad spectrum of disordered systems, from synthetic materials to biological structures guided by stigmergic interactions.
无序超均匀材料因其独特的物理性质而越来越受到关注,这些性质与全局各向同性和局部破坏的取向对称性相关,这使它们有别于传统晶体材料。通过动态空间划分过程,我们生成了无序超均匀细胞结构,其中在六边形区域内出现了独特的五边形和七边形拓扑缺陷模式。微观缺陷动力学由局部拓扑转变引导,这在粘弹性系统中很常见。随着超均匀性的实现,这导致系统结构熵的降低,其标志是某些局部偏好图案的起伏。此外,我们引入了一种弹性超均匀材料,它在连续介质中表现出不断演变的拓扑力学状态。通过振动实验和数值分析,我们展示了能量在这些缺陷周围的局域化,这与我们几何驱动材料固有的拓扑带隙相关。我们认为这种强大的动态机制影响着广泛的无序系统,从合成材料到受 stigmergic 相互作用引导的生物结构。