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Updated: Jul 13, 2026
08:48
High-Resolution Neutron Spectroscopy to Study Picosecond-Nanosecond Dynamics of Proteins and Hydration Water
Published on: April 28, 2022
Slow dynamics and aging in colloidal gels studied by x-ray photon correlation spectroscopy
Andrei Fluerasu1, Abdellatif Moussaïd, Anders Madsen
1European Synchrotron Radiation Facility, Boîte Postale 220, F-38043 Grenoble, France.
Summary
This study reveals colloidal depletion gels undergo a jamming transition during sedimentation, followed by complex aging and eventual collapse due to network deformations.
Area of Science:
- Soft matter physics
- Colloidal science
- Non-equilibrium dynamics
Background:
- Colloidal depletion gels exhibit complex behaviors during sedimentation.
- Understanding nonequilibrium dynamics is crucial for soft matter systems.
Purpose of the Study:
- Investigate the slow, nonequilibrium dynamics of colloidal depletion gels during delayed sedimentation.
- Characterize the jamming transition and subsequent aging processes.
Main Methods:
- Utilized x-ray photon correlation spectroscopy (XPCS) to probe dynamics.
- Analyzed intermediate scattering functions over time.
Main Results:
- Observed a transition from stretched to compressed exponential decays in scattering functions.
- Identified a jamming transition indicative of full aging.
- Documented complex aging behavior following the initial transition.
Conclusions:
- Large-scale network deformations are proposed to trigger unjamming.
- These deformations ultimately lead to the final collapse of the colloidal gel.
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