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Disclinations in nematic liquid crystals are of great interest both theoretically and practically. The ability to create and reconfigure disclinations connecting predetermined points on substrates could enable novel applications such as directed self-assembly of micro/nanoparticles and molecules. In this study, we present a novel approach to design and create disclination interconnects that connect predetermined positions on substrates. We demonstrate that these interconnects can be switched between different states by re-writing photoalignment materials with linearly polarized light, and can be switched between degenerate states using electric fields. The demonstrated strategy allows for creation of multi-scale designer disclination networks and promises potential applications in directed assembly of colloidal micro-/nano-particles, command of active matter, and liquid crystal microfluidics
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Photopatterned Designer Disclination Networks in Nematic Liquid Crystals
Abstract Linear defect‐disclinations are of fundamental interest in understanding complex structures explored by soft matter physics, elementary particles physics, cosmology, and various branches of mathematics. These defects are also of practical importance in materials applications, such as programmable origami, directed colloidal assembly, and command of active matter. Here an effective engineering approach is demonstrated to pattern molecular orientations at two flat confining surfaces that produce complex yet designable networks of singular disclinations of strength 1/2. Depending on the predesigned director patterns at the bounding plates, the produced disclinations are either surface‐anchored, connecting desired sites at the boundaries, or freely suspended in bulk, forming ordered arrays of polygons and wavy lines. The capability is shown to control the radius of curvature, size, and shape of disclinations by varying uniform alignment orientation on one of these confining plates. The capabilities to precisely design and create highly complex 3D disclination networks promise intriguing applications in stimuli‐responsive reconfigurable materials, directed self‐assembly of molecules, micro‐ and nanoparticles, and transport and sorting in microfluidic applications.
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- PAR ID:
- 10366605
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 9
- Issue:
- 16
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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