SURFACE TRANSITION IN A NEMATIC LAYER WITH REVERSE PRETILT

被引:29
作者
KOMITOV, L
LAGERWALL, ST
SPARAVIGNA, A
STEBLER, B
STRIGAZZI, A
机构
[1] POLITECN TORINO, DIPARTIMENTO FIS, GNSM, CISM, I-10129 TURIN, ITALY
[2] POLITECN TORINO, INFM, UNITA TORINO, I-10129 TURIN, ITALY
关键词
D O I
10.1080/15421409208048252
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Recently, a surface induced transition from homeotropic to planar alignment in a nematic layer and the corresponding optical response has been reported /K. Flatischler, L. Komitov, S. T. Lagerwall, B. Stebler, and A. Strigazzi, Mol. Cryst. Liq. Cryst., 198, 119 (1991)/. In the case of surface conditions with reverse pretilt a similar transition from quasi-homeotropic bent alignment to quasi-planar splayed state can be obtained. As known, these two states are topologically incompatible, and therefore the transition is accompanied by nucleation of pi-disclination lines, and even is reversible, it exhibits a big hysteresis. Moreover, it can be driven not only by temperature but also by an applied electric field, using a nematic with negative dielectric anisotropy. A simple theoretical description of such an alignment transition is presented.
引用
收藏
页码:197 / 217
页数:21
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