Lane formation in gravitationally driven colloid mixtures consisting of up to three different particle sizes

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Kay Hofmann - , University of Konstanz, Johannes Gutenberg University Mainz (Author)
  • Marc Isele - , University of Konstanz (Author)
  • Artur Erbe - , Institute of Semiconductors and Microsystems, Helmholtz-Zentrum Dresden-Rossendorf (Author)
  • Paul Leiderer - , University of Konstanz (Author)
  • Peter Nielaba - , University of Konstanz (Author)

Abstract

Brownian dynamics simulations are utilized to study segregation phenomena far from thermodynamic equilibrium. In the present study, we expand upon the analysis of binary colloid mixtures and introduce a third particle species to further our understanding of colloidal systems. Gravitationally driven, spherical colloids immersed in an implicit solvent are confined in two-dimensional linear microchannels. The interaction between the colloids is modeled by the Weeks-Chandler-Andersen potential, and the confinement of the colloids is realized by hard walls based on the solution of the Smoluchowski equation in half space. In binary and ternary colloidal systems, a difference in the driving force is achieved by differing colloid sizes but fixed mass density. We observe for both the binary and ternary systems that a driving force difference induces a nonequilibrium phase transition to lanes. For ternary systems, we study the tendency of lane formation to depend on the diameter of the medium-sized colloids. Here we find a sweet spot for lane formation in ternary systems. Furthermore, we study the interaction of two differently sized colloids at the channel walls. Recently we observed that driven large colloids push smaller colloids to the walls. This results in small particle lanes at the walls at early simulation times. In this work we additionally find that thin lanes are unstable and dissolve over very long time frames. Furthermore, we observe a connection between lane formation and the nonuniform distribution of particles along the channel length. This nonuniform distribution occurs either alongside lane formation or in shared lanes (i.e., lanes consisting of two colloid types).

Details

Original languageEnglish
Article number064601
JournalPhysical Review E
Volume109
Issue number6
Publication statusPublished - Jun 2024
Peer-reviewedYes

External IDs

PubMed 39020999