在散装金属玻璃中间歇性集群动态和时间分数扩散
Birte Riechers1, Amlan Das2,3, Eric Dufresne4
1Federal Institute of Materials Research and Testing (BAM), Unter den Eichen 87, 12205, Berlin, Germany.
Nature communications
|August 3, 2024
概括
金属玻璃的物理衰老揭示了异常运输. 我们在长时间范围内观察到过渡到权力法行为,挑战传统的扩散模型并突出复杂,非单调的衰老动态.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 物理化学 物理化学
背景情况:
- 玻璃状固体经历物理衰老,过渡到较低能量的状态.
- 描述结构放松时间对于理解时间依赖性质至关重要.
研究的目的:
- 在金属玻璃中的物理老化过程中研究原子尺度的微观结构重组.
- 为了确定控制放松过程在延长时间尺度上的传输机制.
主要方法:
- 连贯的X射线散射实验超过30万秒,以跟踪原子重组.
- 原子模拟用于补充实验观测.
主要成果:
- 证明了亚扩散异常传输和时间分数扩散的出现.
- 观察到从伸展指数转变到强度定律行为在长时间的 decorrelation 时间.
- 揭示了集体和间歇性的原子运动.
结论:
- 为经典的伸展指数式放松提供了物理基础.
- 在金属玻璃中发现了一种新的权力法治理集体运输制度.
- 挑战了同质衰老和原子扩散的传统框架.
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