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Updated: May 26, 2026
11:38
Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
Published on: April 19, 2018
Discontinuous percolation transitions in real physical systems.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 21, 2011
Summary
We found that in diffusion-limited cluster aggregation, suppressed cluster growth leads to a sudden increase in giant cluster size, causing a discontinuous percolation transition. This behavior is observed in sol-gel transitions and related physical systems.
Area of Science:
- Physical Chemistry
- Statistical Mechanics
- Materials Science
Background:
- Sol-gel transitions involve cluster aggregation.
- Percolation transitions (PTs) are critical phenomena in aggregation processes.
- Understanding cluster dynamics is key to controlling material properties.
Purpose of the Study:
- To investigate discontinuous percolation transitions in diffusion-limited cluster aggregation.
- To analyze the role of cluster mobility and size-dependent velocity in aggregation dynamics.
- To explore tricritical behavior and determine the tricritical point in this model.
Main Methods:
- Modeling diffusion-limited cluster aggregation with a focus on the number of aggregation events as occupied bonds.
- Analyzing Brownian particle dynamics where cluster velocity scales as v(s)~s(η) with η=-0.5.
- Employing an asymmetric Smoluchowski equation to study tricritical behavior.
Main Results:
- Discontinuous percolation transitions are observed due to suppressed growth of larger clusters.
- Near the percolation threshold, merging of suppressed clusters leads to a drastic increase in giant cluster size.
- Tricritical behavior was studied by varying the parameter η.
Conclusions:
- The diffusion-limited cluster aggregation model exhibits discontinuous percolation transitions under specific conditions.
- Cluster mobility significantly influences aggregation dynamics and the nature of the percolation transition.
- The study provides insights into controlling aggregation processes and understanding critical phenomena in physical systems.
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