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Updated: May 18, 2026
09:32
Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Nonequilibrium static diverging length scales on approaching a prototypical model glassy state
Adam B Hopkins1, Frank H Stillinger, Salvatore Torquato
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 26, 2012
Summary
Maximally random jammed states, a type of glass, show precursors to jamming and growing length scales. These overcompressed sphere packings are inherently nonequilibrium, even before reaching the critical jammed state.
Area of Science:
- Physics
- Materials Science
- Statistical Mechanics
Background:
- Maximally random jammed states of hard spheres serve as archetypal models for glassy systems.
- Understanding the behavior of these systems near the jamming transition is crucial for condensed matter physics.
Purpose of the Study:
- To investigate the small wavenumber (k) behavior of the structure factor S(k) in overcompressed hard-sphere packings.
- To identify precursors to the glassy jammed state and associated length scales as a function of density.
- To characterize the nonequilibrium nature of these packings.
Main Methods:
- Analysis of the structure factor S(k) at small wavenumbers (k).
- Calculation of density-dependent properties for million-sphere packings.
- Definition and application of a nonequilibrium index (X).
Main Results:
- A precursor to the glassy jammed state was observed well before the jamming density.
- Two growing length scales, associated with the direct correlation function and the structure factor, were identified.
- These length scales were found to diverge at the critical jammed state.
- The packings were demonstrated to be intrinsically nonequilibrium.
Conclusions:
- The study reveals pre-jamming phenomena and diverging length scales in hard-sphere glasses.
- The findings highlight the nonequilibrium nature of these systems.
- The results have implications for understanding supercooled liquids and other disordered materials.
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