Dynamics of colloidal particles with capillary interactions

Abstract

We investigate the dynamics of colloids at a fluid interface driven by attractive capillary interactions. At submillimeter length scales, the capillary attraction is formally analogous to two-dimensional gravity. In particular it is a non-integrable interaction and it can be actually relevant for collective phenomena in spite of its weakness at the level of the pair potential. We introduce a mean-field model for the dynamical evolution of the particle number density at the interface. For generic values of the physical parameters the homogeneous distribution is found to be unstable against large-scale clustering driven by the capillary attraction. We also show that for the instability to be observable, the appropriate values for the relevant parameters (colloid radius, surface charge, external electric field, etc.) are experimentally well accessible. Our analysis contributes to current studies of the structure and dynamics of systems governed by long-ranged interactions and points towards their experimental realizations via colloidal suspensions.

Matches version accepted for publication. New refs. added, misprints corrected in figs.6,8,9,10

References in corpus (18)

• Statistical mechanics and dynamics of solvable models with long-range interactions
• Towards granular hydrodynamics in two-dimensions
• Ordered droplet structures at the liquid crystal surface and elastic-capillary colloidal interactions
• Ellipsoidal particles at fluid interfaces
• Thermodynamics and collapse of self-gravitating Brownian particles in D dimensions
• Effective capillary interaction of spherical particles at fluid interfaces
• Anisotropic Capillary Interactions and Jamming of Colloidal Particles Trapped at a Liquid-Fluid Interface
• Charge renormalization for effective interactions of colloids at water interfaces
• Electric-field induced capillary interaction of charged particles at a polar interface
• Computer simulations of two-dimensional melting with dipole-dipole interactions
• Force balance of particles trapped at fluid interfaces
• Effective interactions and phase behaviour for a model clay suspension in an electrolyte
• Attractions between charged colloids at water interfaces
• Multipolar expansion of the electrostatic interaction between charged colloids at interfaces
• Jeans type analysis of chemotactic collapse
• Effective interactions of colloids on nematic films
• Phase transitions in self-gravitating systems and bacterial populations with a screened attractive potential
• Capillary-induced interactions between colloids at an interface

Cited by in corpus (17)

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• Universal threshold for the dynamical behavior of lattice systems with long-range interactions
• Brownian particles with long and short range interactions
• Shock waves in capillary collapse of colloids: a model system for two--dimensional screened Newtonian gravity
• Long-range gravitational-like interaction in a neutral atomic cold gas
• Instability of a uniformly collapsing cloud of classical and quantum self-gravitating Brownian particles
• Capillary interactions in Pickering emulsions
• Elastocapillary self-folding: buckling, wrinkling and collapse of floating filaments
• Exact analytical solution of the collapse of self-gravitating Brownian particles and bacterial populations at zero temperature
• Collective dynamics of colloids at fluid interfaces
• Self-assembly of repulsive interfacial particles via collective sinking
• Stability and dynamics of magnetocapillary interactions
• Gravitational phase transitions with an exclusion constraint in position space
• Phase coexistence in a monolayer of active particles induced by Marangoni flows
• Capillary interactions between soft capsules protruding through thin fluid films
• Signature of the time-dependent hydrodynamic interactions on the collective diffusion in colloidal monolayers
• Non-mean-field effects in systems with long-range forces in competition