无形固体的顺序指标:结构,超均性,以及对超稳定的玻璃的含义
Ding Xu1, Qinyi Liao2,3, Ning Xu1
1Hefei National Research Center for Physical Sciences at the Microscale and Department of Physics, University of Science and Technology of China, Hefei 230026, P. R. China. ningxu@ustc.edu.cn.
Soft matter
|October 10, 2025
概括
研究人员开发了一个新的顺序参数来分析无序的固体和玻璃过渡. 这个参数揭示了粒子排列如何影响稳定性和密度波动,为超稳定的玻璃提供了洞察力.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 统计力学 统计力学
背景情况:
- 鉴定无序固体和玻璃转变的特征是具有挑战性的,因为缺乏远程秩序.
- 了解局部结构和宏观性质之间的关系至关重要.
研究的目的:
- 为无序固体提出一个新的结构顺序参数.
- 研究2D硬颗粒包装在干扰过渡附近的结构秩序和超均性的演变.
- 将局部秩序波动与热力学稳定性和密度波动联系起来.
主要方法:
- 开发一个包含多个旋转对称性的新顺序参数.
- 在阻塞过渡线沿着硬颗粒的2D无序包装的统计分析.
- 检查富含颗粒的状态及其与包装分数和超均性的相关性.
主要成果:
- 观察到从无序到有序颗粒丰富的状态的过渡随着包装分数的增加.
- 在超均性中发现了一种不寻常的非单调变化.
- 发现高包装分数状态表现出最小的长波长密度波动.
结论:
- 新的顺序参数有效地将局部顺序波动与热力学稳定性和密度波动联系起来.
- 超稳定的玻璃,虽然通过单一对称度的措施在全球上是无序的,但富含有序的粒子,并表现出类似晶体的密度波动.
- 这项工作为超稳定玻璃的结构特征提供了新的视角.
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