Manifestation of biquadratic coupling in the smectic C* phase soft mode dielectric response
作者:
F. Gouda,
T. Carlsson,
G. Andersson,
S.T. Lagerwall,
B. Stebler,
期刊:
Liquid Crystals
(Taylor Available online 1994)
卷期:
Volume 16,
issue 2
页码: 315-322
ISSN:0267-8292
年代: 1994
DOI:10.1080/02678299408029155
出版商: Taylor & Francis Group
数据来源: Taylor
摘要:
The soft mode dielectric response of three ferroelectric chiral smectic C* substances is studied in the vicinity of the smectic C*-smectic A* phase transition. For some substances the soft mode dielectric strength exhibits a pronounced anomaly in the C* phase just below the phase transition. We show how this anomaly can be systematically correlated with a corresponding anomaly in the experimentally determined ratio of spontaneous polarization over tilt. By comparing the experimental results with the theoretical predictions of an extended Landau model, we demonstrate how the crossover behaviour of the system can be interpreted as being the consequence of the presence of a biquadratic coupling between tilt and polarization in the Landau free-energy of the system.
点击下载:
PDF (436KB)
返 回