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Dynamical Spreading and Memory Retention of Particle Suspensions under Power Law Potential.
Ido Fanto1, Yuval Rosenblum1, Ori Harel1
1Tel Aviv University, School of Physics and Astronomy and the Center for Physics and Chemistry of Living Systems, Tel Aviv 6997801, Israel.
Physical Review Letters
|July 7, 2026
Summary
Particle suspensions spread uniformly in a self-similar pattern, with radius growth independent of system dimension. Experiments with magnetized colloids confirm this, revealing memory effects below a critical power threshold.
Area of Science:
- Soft matter physics
- Colloidal science
- Dynamic systems
Background:
- Understanding particle suspension dynamics is crucial in fluid mechanics and materials science.
- Repulsive potentials govern particle interactions and emergent collective behaviors.
Purpose of the Study:
- To investigate the dynamic spreading of particle suspensions under repulsive power-law potentials.
- To predict and experimentally verify self-similar spreading behavior.
- To explore pattern formation and memory effects in driven colloidal systems.
Main Methods:
- Theoretical prediction of self-similar spreading dynamics.
- Experimental realization using magnetized colloidal particles with tunable dipolar repulsion.
- Numerical simulations to corroborate experimental findings and explore parameter space.
Main Results:
- The suspension spreads in a self-similar manner, with radius growth power-law independent of system dimension.
- Experimental confirmation using magnetized colloids.
- Numerical simulations revealed a critical power-law exponent below which particles accumulate at the perimeter, retaining pattern memory.
Conclusions:
- Dynamic spreading of particle suspensions exhibits universal self-similar behavior.
- A critical exponent governs a transition to pattern memory effects.
- The initial particle distribution can encode the future structure of the evolving system.
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