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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Bonded boojum-colloids in nematic liquid crystals
Zahra Eskandari1, Nuno M Silvestre, Margarida M Telo da Gama
1Centro de Física Teórica e Computacional, Universidade de Lisboa, Avenida Professor Gama Pinto 2, PT-1649-003 Lisboa, Portugal.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 18, 2013
Summary
We studied bonded boojum-colloids in liquid crystals, finding they form stable linear chains. These chains are the preferred structure, even under confinement, especially when twist deformations are minimal.
Area of Science:
- Soft Matter Physics
- Materials Science
- Colloid Science
Background:
- Boojum-colloids are topological defects in liquid crystals.
- Their interactions and self-assembly are crucial for material properties.
Purpose of the Study:
- Investigate the formation and stability of bonded boojum-colloid structures.
- Analyze the influence of twist deformations and confinement on these configurations.
Main Methods:
- Theoretical modeling of colloid-liquid crystal interactions.
- Analysis of defect-mediated bonding and elastic constants.
Main Results:
- Bonded boojum-colloids form linear chains aligned with the nematic director.
- This bonded configuration is the global minimum, particularly in systems favoring twist.
- Confinement favors unbonded configurations, but bonded structures remain stable for small twist elastic constants.
Conclusions:
- Bonded boojum-colloids exhibit stable linear chain formation.
- Elastic properties, specifically twist elastic constants, dictate the stability of bonded versus unbonded configurations under confinement.
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