6533b856fe1ef96bd12b30af
RESEARCH PRODUCT
Measurement of elastic forces between iron colloidal particles in a nematic liquid crystal.
Françoise GiulieriS. LacisGeorges BossisAnne Marie ChazeC. Noelsubject
Models MolecularMechanical equilibriumMaterials scienceIronRings of SaturnHomeotropic alignmentGeneral Physics and AstronomyAnchoringlaw.inventionColloidOpticsElectromagnetic FieldsLiquid crystallawComputer SimulationColloidsParticle SizeRange (particle radiation)Condensed matter physicsbusiness.industryElasticityMagnetic fieldLiquid CrystalsNanostructuresModels ChemicalStress Mechanicalbusinessdescription
The forces that arise between two iron particles in a nematic liquid crystal with a strong homeotropic anchoring were studied. For the first time, the short range repulsive force resulting from the presence of a hedgehog defect between two particles was precisely determined thanks to application of a small magnetic field and observation of the equilibrium position resulting from the balance between the elastic and magnetic forces. Above a given threshold force, the particles stuck together whereas the hedgehog defect was expelled and transformed into a Saturn ring located between the particles. The attractive part of the interparticle force was determined with the same method on the entire range of separation distances; we found that the equilibrium distance between two particles was $r=1.19\ifmmode\pm\else\textpm\fi{}0.05$ $⟨d⟩$ ($⟨d⟩$ was the average diameter of the pair of particles).
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2006-06-01 | Physical review letters |