Localization dynamics of fluids in random confinement

Abstract

The dynamics of two-dimensional fluids confined within a random matrix of obstacles is investigated using both colloidal model experiments and molecular dynamics simulations. By varying fluid and matrix area fractions in the experiment, we find delocalized tracer particle dynamics at small matrix area fractions and localized motion of the tracers at high matrix area fractions. In the delocalized region, the dynamics is subdiffusive at intermediate times, and diffusive at long times, while in the localized regime, trapping in finite pockets of the matrix is observed. These observations are found to agree with the simulation of an ideal gas confined in a weakly correlated matrix. Our results show that Lorentz gas systems with soft interactions are exhibiting a smoothening of the critical dynamics and consequently a rounded delocalization-to-localization transition.

5 pages, 3 figures

References in corpus (11)

• Anomalous transport in the crowded world of biological cells
• Fundamental questions relating to ion conduction in disordered solids
• Liquid-glass transition of a fluid confined in a disordered porous matrix: A mode-coupling theory
• Mode-coupling theory for the slow collective dynamics of fluids adsorbed in disordered porous media
• Single-particle and collective slow dynamics of colloids in porous confinement
• The Localization Transition of the Two-Dimensional Lorentz Model
• Tagged-particle dynamics in a fluid adsorbed in a disordered porous solid: interplay between the diffusion-localization and liquid-glass transitions
• Mode-coupling theory predictions for the dynamical transitions of the partly pinned fluid systems
• Impact of random obstacles on the dynamics of a dense colloidal fluid
• Dynamic arrest of colloids in porous environments: disentangling crowding and confinement
• Dynamic arrest in model porous media -- intermediate scattering functions

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