Chiral motion in colloidal electrophoresis
arXiv:1912.13090 · doi:10.1103/PhysRevE.101.062608
Abstract
Asymmetrically charged, nonspherical colloidal particles in general perform complex rotations and oblique motions under an electric field. The interplay of electrostatic and hydrodynamic forces complicate the prediction of these motions. We demonstrate a method of calculating the body tensors that dictate translational and rotational velocity vectors arising from an external electric field. We treat insulating, rigid bodies in the linear-response regime, with indefinitely small electrostatic screening length. The method represents the body as an assembly of point sources of both hydrodynamic drag and surface electric field. We demonstrate agreement with predicted electrophoretic mobility to within a few percent for several shapes with uniform and nonuniform charge. We demonstrate strong chiral twisting motions for colloidal bodies of symmetrical realistic shapes. The method applies more generally to active colloidal swimmers.
arXiv comment14 pages
References in corpus (10)
- Emergence of macroscopic directed motion in populations of motile colloids
- Topological mechanics of gyroscopic metamaterials
- Screening, Hyperuniformity, and Instability in the Sedimentation of Irregular Objects
- Chiral sedimentation of extended objects in viscous media
- Hydrodynamic Interactions between Two Forced Objects of Arbitrary Shape: I Effect on Alignment
- Full alignment of colloidal objects by programmed forcing
- Hydrodynamic Interactions between Two Forced Objects of Arbitrary Shape: II Relative Translation
- Orientational ordering of colloidal dispersions by application of time dependent external forces
- Predicting tensorial electrophoretic effects in asymmetric colloids
- Criterion for noise-induced synchronization: application to colloidal alignment