Computer simulation of topological defects around a colloidal particle or droplet dispersed in a nematic host
We use molecular dynamics to study the ordering of a nematic liquid crystal around a spherical particle or droplet. Homeotropic boundary conditions and strong anchoring create a hedgehog (radial point defect) director configuration on the particle surface and in its vicinity; this topological defect...
Main Authors: | , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2001
|
Subjects: | |
Online Access: | http://discovery.ucl.ac.uk/1407463/ |
id |
ftucl:oai:eprints.ucl.ac.uk.OAI2:1407463 |
---|---|
record_format |
openpolar |
spelling |
ftucl:oai:eprints.ucl.ac.uk.OAI2:1407463 2023-05-15T18:22:35+02:00 Computer simulation of topological defects around a colloidal particle or droplet dispersed in a nematic host Andrienko, D Germano, G Allen, MP 2001-04 http://discovery.ucl.ac.uk/1407463/ eng eng Physical Review E , 63 (4) , Article 041701. (2001) Article 2001 ftucl 2016-03-03T23:11:43Z We use molecular dynamics to study the ordering of a nematic liquid crystal around a spherical particle or droplet. Homeotropic boundary conditions and strong anchoring create a hedgehog (radial point defect) director configuration on the particle surface and in its vicinity; this topological defect is canceled by nearby defect structures in the surrounding liquid crystal, so as to give a uniform director field at large distances. We observe three defect structures for different particle sizes: a quadrupolar one with a ring defect surrounding the particle in the equatorial plane; a dipolar one with a satellite defect at the north or south pole; and a transitional, nonequatorial, ring defect. These observations are broadly consistent with the predictions of the simplest elastic theory. By studying density and order-parameter maps, we are able to examine behavior near the particle surface, and in the disclination core region, where the elastic theory is inapplicable. Despite the relatively small scale of the inhomogeneities in our systems, the simple theory gives reasonably accurate predictions of the variation of defect position with particle size. Article in Journal/Newspaper South pole University College London: UCL Discovery South Pole |
institution |
Open Polar |
collection |
University College London: UCL Discovery |
op_collection_id |
ftucl |
language |
English |
description |
We use molecular dynamics to study the ordering of a nematic liquid crystal around a spherical particle or droplet. Homeotropic boundary conditions and strong anchoring create a hedgehog (radial point defect) director configuration on the particle surface and in its vicinity; this topological defect is canceled by nearby defect structures in the surrounding liquid crystal, so as to give a uniform director field at large distances. We observe three defect structures for different particle sizes: a quadrupolar one with a ring defect surrounding the particle in the equatorial plane; a dipolar one with a satellite defect at the north or south pole; and a transitional, nonequatorial, ring defect. These observations are broadly consistent with the predictions of the simplest elastic theory. By studying density and order-parameter maps, we are able to examine behavior near the particle surface, and in the disclination core region, where the elastic theory is inapplicable. Despite the relatively small scale of the inhomogeneities in our systems, the simple theory gives reasonably accurate predictions of the variation of defect position with particle size. |
format |
Article in Journal/Newspaper |
author |
Andrienko, D Germano, G Allen, MP |
spellingShingle |
Andrienko, D Germano, G Allen, MP Computer simulation of topological defects around a colloidal particle or droplet dispersed in a nematic host |
author_facet |
Andrienko, D Germano, G Allen, MP |
author_sort |
Andrienko, D |
title |
Computer simulation of topological defects around a colloidal particle or droplet dispersed in a nematic host |
title_short |
Computer simulation of topological defects around a colloidal particle or droplet dispersed in a nematic host |
title_full |
Computer simulation of topological defects around a colloidal particle or droplet dispersed in a nematic host |
title_fullStr |
Computer simulation of topological defects around a colloidal particle or droplet dispersed in a nematic host |
title_full_unstemmed |
Computer simulation of topological defects around a colloidal particle or droplet dispersed in a nematic host |
title_sort |
computer simulation of topological defects around a colloidal particle or droplet dispersed in a nematic host |
publishDate |
2001 |
url |
http://discovery.ucl.ac.uk/1407463/ |
geographic |
South Pole |
geographic_facet |
South Pole |
genre |
South pole |
genre_facet |
South pole |
op_source |
Physical Review E , 63 (4) , Article 041701. (2001) |
_version_ |
1766201998780137472 |