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Patterning of Microorganisms and Microparticles through Sequential Capillarity-assisted Assembly
Published on: November 4, 2021
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Electric field controlled columnar and planar patterning of cholesteric colloids.
G D'Adamo1, D Marenduzzo2, C Micheletti1
1SISSA, International School for Advanced Studies, via Bonomea 265, I-34136 Trieste, Italy.
Physical Review Letters
|May 16, 2015
Summary
Scientists explored how colloidal particles in liquid crystals respond to electric fields. They demonstrated control over particle arrangements, creating diverse structures like Saturn rings and columnar arrays for advanced material self-assembly.
Area of Science:
- Soft matter physics
- Colloid science
- Liquid crystal research
Background:
- Cholesteric liquid crystals exhibit unique phase behaviors.
- Colloidal particle dispersions are crucial in advanced materials.
- Electric fields can influence liquid crystal and particle dynamics.
Purpose of the Study:
- To investigate the behavior of colloidal particle dispersions in cholesteric liquid crystals under time-dependent electric fields.
- To explore the manipulation of particle self-assembly and structure formation.
- To identify novel kinetic pathways and metastable equilibrium states.
Main Methods:
- Applying time-dependent electric fields with controlled amplitude and waveform.
- Observing and analyzing particle dispersion behavior and structural evolution.
- Characterizing the resulting complex particle arrangements and defect networks.
Main Results:
- Reproducible driving of the system out of equilibrium into various kinetic pathways.
- Navigation through a glassy free energy landscape with multiple metastable equilibria.
- Formation of diverse structures including Saturn rings, amorphous defect networks, and disclination loop stacks.
- Induction of particle alignment into columnar arrays via defect-mediated forces.
- Observation of particle repositioning within the liquid crystal plane.
Conclusions:
- Time-dependent electric fields offer precise control over colloidal self-assembly in liquid crystals.
- The study reveals pathways to engineer complex soft matter architectures.
- Findings open new avenues for controlled patterning in colloid-liquid crystal composites.
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