Anchoring transition in confined discotic columnar liquid crystal films

被引：22

作者：

Brunet, Thomas ^{[1
]}

Thiebaut, Olivier ^{[1
]}

Charlet, Emilie ^{[1
]}

Bock, Harald ^{[1
]}

Kelber, Julien ^{[1
]}

Grelet, Eric ^{[1
]}

机构：

[1] Univ Bordeaux, Ctr Rech Paul Pascal, CNRS, F-33600 Pessac, France

来源：

EPL | 2011年 / 93卷 / 01期

关键词：

GROWTH; PHTHALOCYANINE; ALIGNMENT;

D O I：

10.1209/0295-5075/93/16004

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We report the achievement of ultrathin films (down to 25 nm thick) of thermotropic columnar liquid crystals in homeotropic alignment (columns normal to the interface) confined between a glass slide and a thin metallic electrode (about 150nm thick). The face-on orientation of the discotic compound is obtained by anchoring transition of a columnar liquid crystalline phase from a degenerate planar orientation to the homeotropic alignment without any phase transition to the isotropic liquid phase. The kinetic dependence on temperature of such anchoring transition is investigated revealing various diffusive growth regimes of the homeotropic domains. Finally, confining effects are also considered by varying the thickness of the columnar liquid crystal film to reach the typical value required in organic solar cells thus demonstrating the reliability of such alignment process in a photovoltaic context. Copyright (C) EPLA, 2011

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页数：6

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