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Updated: Apr 5, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
9.1K
Thermal fluctuations, mechanical response, and hyperuniformity in jammed solids.
Atsushi Ikeda1, Ludovic Berthier2
1Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto, Japan.
Summary
Thermal fluctuations impact jamming transitions in particle systems. Their relative ratio quantifies jamming criticality, and mechanical moduli can be measured from particle positions, revealing hyperuniformity unrelated to compressibility.
Area of Science:
- Physics
- Materials Science
- Statistical Mechanics
Background:
- Jamming is a geometric phase transition in dense particle systems without temperature.
- Understanding the influence of thermal fluctuations on jamming signatures is crucial.
Purpose of the Study:
- To analyze the effect of thermal fluctuations on jamming transition signatures.
- To identify quantitative signatures of jamming criticality and explore hyperuniformity.
Main Methods:
- Utilized computer simulations to model dense particle systems.
- Analyzed scaling laws for bulk and shear moduli under varying thermal fluctuations.
- Investigated fluctuation-dissipation relations and spatial correlations of particle displacements.
Main Results:
- Scaling laws for moduli are relevant only at extremely low thermal fluctuations; their ratio serves as a jamming criticality signature.
- Thermally induced fluctuations and mechanical responses near jamming obey equilibrium fluctuation-dissipation relations.
- Fluctuations of particle displacements are spatially correlated, with diverging transverse and longitudinal correlation lengths near jamming.
- Frozen density fluctuations exhibit nearly hyperuniform behavior, independent of compressibility.
Conclusions:
- Jamming criticality can be quantitatively assessed using the ratio of moduli, even with thermal fluctuations.
- Mechanical moduli are measurable from particle positions in unperturbed packings, simplifying analysis.
- Hyperuniformity in jammed packings is robust and unrelated to compressibility, with thermal fluctuations not hindering its observation.
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