6533b83afe1ef96bd12a7b58
RESEARCH PRODUCT
Colloidal layers in magnetic fields and under shear flow
Peter KeimChristos N. LikosRené MessinaGeorg MaretUrs GasserThomas PalbergNorman HoffmannRoy GoldbergChristoph EisenmannHartmut Löwensubject
Condensed matter physicsChemistryEmulsions and suspensionsColloidal crystalCondensed Matter PhysicsSolid-liquid transitionsMagnetic fieldCondensed Matter::Soft Condensed MatterColloidShear (geology)MonolayerGeneral Materials Scienceddc:530Colloidspacs:82.70.Dd 64.70.D 82.70.KjAnisotropyShear flowSuperparamagnetismdescription
The behaviour of colloidal mono- and bilayers in external magnetic fields and under shear is discussed and recent progress is summarized. Superparamagnetic colloidal particles form monolayers when they are confined to a air–water interface in a hanging water droplet. An external magnetic field allows us to tune the strength of the mutual dipole–dipole interaction between the colloids and the anisotropy of the interaction can be controlled by the tilt angle of the magnetic field relative to the surface normal of the air–water interface. For sufficiently large magnetic field strength crystalline monolayers are found. The role of fluctuations in these two-dimensional crystals is discussed. Furthermore, clustering phenomena in binary mixtures of superparamagnetic particles forming fluid monolayers are predicted. Finally, we address sheared colloidal bilayers and find that the orientation of confined colloidal crystals can be tailored by a previously applied shear direction.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2005-10-28 |