{"title":"近晶液晶薄膜中的一维图案和拓扑缺陷","authors":"B. Zappone, E. Lacaze","doi":"10.1080/21680396.2022.2076748","DOIUrl":null,"url":null,"abstract":". Smectic liquid crystals exhibit a remarkable ability to self-organize into a variety of textures, patterns, and arrays extending over large surface areas with microscale periodicity. These structures provide a useful platform for the bottom-up fabrication of microdevices and functional materials, such as microlens arrays and nanoparticle templates. Periodic structures appear in response to a conflict of director alignment created within the smectic film by external fields such as hybrid (planar-homeotropic) anchoring conditions at the film interfaces or an electric field applied normal to the surface anchoring direction. In this article, we review the formation, structure, and applications of one-dimensional (1d) patterns obtained in response to a director bend, typically induced by unidirectional hybrid anchoring conditions in thin films or under applied electric fields. Compared to lattices of focal conic, 1d patterns harbor an unusual array of topological defects, including disclination and dislocation lines, grain boundaries, and curvature walls, running along periodically spaced and bend-free cylindrical stacks of smectic layers. These defects, most of which have been described by Maurice Kleman, appear to drive the structural evolution of 1d patterns as a function of the film thickness. Under unidirectional hybrid anchoring, the defects are oriented perpendicular to the planar anchoring direction and provide highly anisotropic templates for building ordered networks of close-packed nanoparticles. Moreover, the array formation at the transition from the nematic to the smectic phase is intimately connected to the smectic phase frustration by bend distortions, producing an “intermediate” smectic with partial penetration of the bend distortion through undercooled nematic domains","PeriodicalId":18087,"journal":{"name":"Liquid Crystals Reviews","volume":null,"pages":null},"PeriodicalIF":4.8000,"publicationDate":"2022-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":"{\"title\":\"One-dimensional patterns and topological defects in smectic liquid crystal films\",\"authors\":\"B. Zappone, E. Lacaze\",\"doi\":\"10.1080/21680396.2022.2076748\",\"DOIUrl\":null,\"url\":null,\"abstract\":\". Smectic liquid crystals exhibit a remarkable ability to self-organize into a variety of textures, patterns, and arrays extending over large surface areas with microscale periodicity. These structures provide a useful platform for the bottom-up fabrication of microdevices and functional materials, such as microlens arrays and nanoparticle templates. Periodic structures appear in response to a conflict of director alignment created within the smectic film by external fields such as hybrid (planar-homeotropic) anchoring conditions at the film interfaces or an electric field applied normal to the surface anchoring direction. In this article, we review the formation, structure, and applications of one-dimensional (1d) patterns obtained in response to a director bend, typically induced by unidirectional hybrid anchoring conditions in thin films or under applied electric fields. Compared to lattices of focal conic, 1d patterns harbor an unusual array of topological defects, including disclination and dislocation lines, grain boundaries, and curvature walls, running along periodically spaced and bend-free cylindrical stacks of smectic layers. These defects, most of which have been described by Maurice Kleman, appear to drive the structural evolution of 1d patterns as a function of the film thickness. Under unidirectional hybrid anchoring, the defects are oriented perpendicular to the planar anchoring direction and provide highly anisotropic templates for building ordered networks of close-packed nanoparticles. Moreover, the array formation at the transition from the nematic to the smectic phase is intimately connected to the smectic phase frustration by bend distortions, producing an “intermediate” smectic with partial penetration of the bend distortion through undercooled nematic domains\",\"PeriodicalId\":18087,\"journal\":{\"name\":\"Liquid Crystals Reviews\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.8000,\"publicationDate\":\"2022-05-16\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"3\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Liquid Crystals Reviews\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://doi.org/10.1080/21680396.2022.2076748\",\"RegionNum\":3,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Liquid Crystals Reviews","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1080/21680396.2022.2076748","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
One-dimensional patterns and topological defects in smectic liquid crystal films
. Smectic liquid crystals exhibit a remarkable ability to self-organize into a variety of textures, patterns, and arrays extending over large surface areas with microscale periodicity. These structures provide a useful platform for the bottom-up fabrication of microdevices and functional materials, such as microlens arrays and nanoparticle templates. Periodic structures appear in response to a conflict of director alignment created within the smectic film by external fields such as hybrid (planar-homeotropic) anchoring conditions at the film interfaces or an electric field applied normal to the surface anchoring direction. In this article, we review the formation, structure, and applications of one-dimensional (1d) patterns obtained in response to a director bend, typically induced by unidirectional hybrid anchoring conditions in thin films or under applied electric fields. Compared to lattices of focal conic, 1d patterns harbor an unusual array of topological defects, including disclination and dislocation lines, grain boundaries, and curvature walls, running along periodically spaced and bend-free cylindrical stacks of smectic layers. These defects, most of which have been described by Maurice Kleman, appear to drive the structural evolution of 1d patterns as a function of the film thickness. Under unidirectional hybrid anchoring, the defects are oriented perpendicular to the planar anchoring direction and provide highly anisotropic templates for building ordered networks of close-packed nanoparticles. Moreover, the array formation at the transition from the nematic to the smectic phase is intimately connected to the smectic phase frustration by bend distortions, producing an “intermediate” smectic with partial penetration of the bend distortion through undercooled nematic domains
期刊介绍:
Liquid Crystals Reviews publishes review articles on all aspects of liquid crystal fundamentals and applied science, including experimental and theoretical studies of physical and chemical properties, molecular design and synthesis and engineering of liquid crystal devices. The Journal fosters cross-disciplinary exchange of ideas, encouraging authors to present material at a level accessible to specialists from other fields of science and engineering. Liquid Crystals Reviews provides the scientific community, in both academia and industry, with a publication of standing, guaranteed by the Editors and by the International Editorial Board who are active scientists in the worldwide liquid crystal community.