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Area of Science:

  • Soft matter physics
  • Materials science
  • Nematic liquid crystals

Background:

  • Colloidal dispersions in liquid crystals enable self-assembly of composite materials.
  • Particle-induced topological defects significantly influence material properties and structure.

Purpose of the Study:

  • To demonstrate patterning of bulk and surface defects in nematic fluids.
  • To explore the influence of colloidal particle topology on defect configurations.

Main Methods:

  • Utilized two-photon photopolymerization to fabricate knot-shaped microparticles.
  • Dispersed these microparticles in nematic fluids to observe defect formation.

Main Results:

  • Achieved patterned bulk and surface defects by tuning particle topology.
  • Observed knotted, linked, and topologically non-trivial field configurations.
  • Experimental results align with theoretical predictions based on elastic free energy minimization.

Conclusions:

  • Tuning colloidal particle topology offers a method for controlling topological defects in liquid crystals.
  • This approach facilitates the creation of self-assembled topological superstructures and scaffolds.
  • Potential applications in materials science and modeling of topological phenomena.