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Updated: Jan 15, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Order metrics of amorphous solids: structures, hyperuniformity, and implications for ultra-stable glasses
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
Summary
Researchers developed a new order parameter to analyze disordered solids and the glass transition. This parameter reveals how particle arrangements influence stability and density fluctuations, offering insights into ultra-stable glasses.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Statistical Mechanics
Background:
- Characterizing disordered solids and the glass transition is challenging due to the lack of long-range order.
- Understanding the relationship between local structure and macroscopic properties is crucial.
Purpose of the Study:
- To propose a novel structural order parameter for disordered solids.
- To investigate the evolution of structural order and hyperuniformity in 2D hard particle packings near the jamming transition.
- To link local order fluctuations to thermodynamic stability and density fluctuations.
Main Methods:
- Development of a new order parameter incorporating multiple rotational symmetries.
- Statistical analysis of 2D disordered packings of hard particles along the jamming transition line.
- Examination of particle-rich states and their correlation with packing fraction and hyperuniformity.
Main Results:
- Observed a transition from disordered- to ordered-particle-rich states with increasing packing fraction.
- Identified an unusual non-monotonic change in hyperuniformity.
- Found that high packing fraction states exhibit minimal long-wavelength density fluctuations.
Conclusions:
- The new order parameter effectively links local order fluctuations to thermodynamic stability and density fluctuations.
- Ultra-stable glasses, though globally disordered by single symmetry measures, are rich in ordered particles and exhibit crystal-like density fluctuations.
- This work provides a new perspective on the structural characteristics of ultra-stable glasses.
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