In 3D nematic liquid crystals, disclination lines have a range of geometric structures. Locally, they may resemble +1/2 or -1/2 defects in 2D nematic phases, or they may have 3D twist. Here, we analyze the structure in terms of the director deformation modes around the disclination, as well as the nematic order tensor inside the disclination core. Based on this analysis, we construct a vector to represent the orientation of the disclination, as well as tensors to represent higher-order structure. We apply this method to simulations of a 3D disclination arch, and determine how the structure changes along the contour length. We then use this geometric analysis to investigate three types of forces acting on a disclination: Peach-Koehler forces due to external stress, interaction forces between disclination lines, and active forces. These results apply to the motion of disclination lines in both conventional and active liquid crystals.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/d0sm01899f | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Majorana quasiparticles and topological phases in 3D active nematics.
Proc Natl Acad Sci U S A
December 2024
School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom.
Quasiparticles are low-energy excitations with important roles in condensed matter physics. An intriguing example is provided by Majorana quasiparticles, which are equivalent to their antiparticles. Despite being implicated in neutrino oscillations and topological superconductivity, their experimental realizations remain very rare.
View Article and Find Full Text PDFEdge-on anchored discotic liquid crystals in spherical shells: A computational study of the phases and defects.
Phys Rev E
September 2024
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Apdo. Postal 70-360, 04510 México, Ciudad de México, México.
The self-assembly of liquid crystal droplets and shells represents a captivating frontier in soft matter physics, promising precision engineering of functional materials. In this study, we delve into the phase behavior and investigate defect formation patterns in spherical shell-confined discotic liquid crystals (DLCs) through NpT Monte Carlo simulations. These shells are created by confining DLCs between two spherical surfaces, promoting the same anchoring.
View Article and Find Full Text PDFTopology-driven collective dynamics of nematic colloidal entanglement.
Proc Natl Acad Sci U S A
September 2024
Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
Article Synopsis
- Entanglement in soft matter systems is achieved through entangled disclination lines created by colloidal particles in nematic liquid crystals, presenting a new way to study interactions at equilibrium.
- Researchers used experiments and simulations to manipulate these disclination lines, showing that changes in their topology can lead to phenomena like chirality conversion and collective rotation of colloidal particles.
- This approach allows for the programming of colloidal entanglement patterns, enabling the construction of complex structures like double-helix formations, opening doors for the development of smart materials and micromachines.
Coexistence of Defect Morphologies in Three-Dimensional Active Nematics.
Phys Rev Lett
June 2024
Department of Applied Physics and Science Education, Eindhoven University of Technology, Den Dolech 2, 5600 MB Eindhoven, Netherlands.
We establish how active stress globally affects the morphology of disclination lines of a three-dimensional active nematic liquid crystal under chaotic flow. Thanks to a defect detection algorithm based on the local nematic orientation, we show that activity selects a crossover length scale in between the size of small defect loops and that of long and tangled defect lines of fractal dimension 2. This length scale crossover is consistent with the scaling of the average separation between defects as a function of activity.
View Article and Find Full Text PDFRevealing the antipolar order in the antiferroelectric SmZ phase by means of circular alignment.
Sci Rep
July 2024
Institute of Physical Chemistry, University of Stuttgart, 70569, Stuttgart, Germany.
Many ferroelectric nematic liquid crystals, like one of the archetype materials, DIO, do not have a direct paraelectric N to ferroelectric N phase transition, but exhibit yet another phase between N and N. This phase has recently been proposed to be antiferroelectric, with a layered structure of alternating polarization normal to the average director and is sometimes referred to as Smectic Z (SmZ). We have examined the SmZ phase in circularly rubbed (CR) cells, known to discriminate between the polar N and the non-polar N phase from the configuration of disclination lines formed.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!