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Updated: Jul 15, 2026
10:56
Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures
Published on: May 20, 2014
Stripes, clusters, and nonequilibrium ordering for bidisperse colloids with repulsive interactions.
C Reichhardt1, C J Olson Reichhardt
1Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
Summary
Driven colloidal assemblies on random substrates form ordered nonequilibrium states, surpassing equilibrium order. A minimum substrate strength is key for this pattern formation in colloid mixtures.
Area of Science:
- Colloid science
- Soft matter physics
- Materials science
Background:
- Colloidal systems are model systems for studying phase transitions and self-assembly.
- Understanding pattern formation in mixtures is crucial for materials design.
- Equilibrium states often lack the desired order for specific applications.
Purpose of the Study:
- To investigate pattern formation in two-dimensional bidisperse colloidal assemblies.
- To explore the role of driven dynamics and quenched disorder on assembly.
- To compare the order of nonequilibrium states with equilibrium states.
Main Methods:
- Simulations of two-dimensional bidisperse colloidal assemblies with repulsive interactions.
- Utilizing a quenched random substrate to introduce disorder.
- Applying external driving forces to the colloidal system.
Main Results:
- Observed formation of stripe, cluster, and partially crystallized nonequilibrium states.
- Nonequilibrium states exhibited significantly higher order than equilibrium states.
- A minimum substrate strength was identified as necessary for pattern formation.
Conclusions:
- Driven colloidal systems on disordered substrates can form highly ordered nonequilibrium states.
- Quenched disorder combined with driving provides a route to control pattern formation.
- This approach offers new strategies for designing ordered materials from mixtures.
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