Single-file and normal diffusion of magnetic colloids in modulated channels

Abstract

Diffusive properties of interacting magnetic dipoles confined in a parabolic narrow channel and in the presence of a periodic modulated (corrugated) potential along the unconfined direction are studied using Brownian dynamics simulations. We compare our simulation results with the analytical result for the effective diffusion coefficient of a single-particle by Festa and d'Agliano [Physica A 90, 229 (1978)] and show the importance of inter-particle interaction on the diffusion process. We present results for the diffusion of magnetic dipoles as a function of linear density, strength of the periodic modulation and commensurability factor.

Active matter in lateral parabolic confinement: From subdiffusion to superdiffusion

“…Therefore, we see that super and normal diffusion seen at high V 0 is the result of the available space that is left among clusters which allows them to diffuse more swiftly than at the (apparently) SFD picture seen at fig. 4b, (a similar effect was reported for magnetic brownian particles in confinement [24] in which attractive interactions were responsible for the aggregation). In the next section, we study these clusters a little further so that we can to understand their role in the system.…”

Structural orderings of anisotropically confined colloids interacting via a quasi-square-well potential

“…To m ention ju st a few, Yukawa interacting particles in dust plasm a leads to the form ation o f shell [27][28][29][30] and ring structures [31,32], respectively, for two-and three-dim ensional space, both holding a high m echanical stability. A sim ilar setup in tw o spatial dim ensions can be realized for param agnetic colloidal particles [33][34][35], In this case, the external trap can be controlled by optical tw eezers leading to interesting effects like colloidal "explosions" o f dense clusters w hen the confinem ent is released [36] [37,38] and inhom ogeneous m elting [39,40]. R eference [4] has recently dem onstrated that a transition from the liquid phase to the glass phase can occur in colloidal suspension w hen confined by two nearly parallel walls.…”

Diffusive properties of colloidal charged particles in a quasi-one-dimensional confinement

“…(Lucena et al, 2012;Carvalho et al, 2012;Carvalho et al, 2011) for different damping values (Delfau et al, 2011) and different connement intensities and traps in a monodisperse system of interacting particles (Lucena et al, 2012). Single-file diffusion are also present in nature in many different situations such as diffusion experiments with molecules of zeolite (Meier, 1992), in colloids (Konig, 2005;Wei, 2000), charged macroscopic beads (Coupier et al, 2006) and water through molecular-sized channels in membranes (Hernandez, 1992;Morais-Cabral et al, 2001;Doyle et al, 1998) and for magnetic particles and dipoles (Lucena et al, 2014;Galvan-Moya et al, 2014). In SFD, particles are correlated because particle movement induces other particles to move together.…”