NONLINEAR DIELECTRIC SUSCEPTIBILITY IN BLUE PHASES OF CHIRAL LIQUID-CRYSTALS

Citation
L. Longa et al., NONLINEAR DIELECTRIC SUSCEPTIBILITY IN BLUE PHASES OF CHIRAL LIQUID-CRYSTALS, Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals, 303, 1997, pp. 237-247
Citations number
14
Categorie Soggetti
Crystallography
ISSN journal
1058725X
Volume
303
Year of publication
1997
Pages
237 - 247
Database
ISI
SICI code
1058-725X(1997)303:<237:NDSIBP>2.0.ZU;2-8
Abstract
The deformation of the cubic blue phase I along the field changes from dilatation to compression or vice versa when the electric field vecto r is rotated from one crystallographic direction to another. This phen omenon is termed anomalous electrostriction and together with topology of phase diagrams of the blue phases awaits elucidation. Standard the ory of blue phases is not able to explain these observations. Followin g the experiments of Pieranski et al. we generalized the standard theo ry by incorporating a nonlinear dielectric susceptibility tensor (NDS) . It is shown that the distortion of the cubic blue phase I in the pre sence of the NDS may display the anomalous electrostriction, in accord ance with experiment. These results seem to indicate that nonlinear su sceptibility tensor is a relevant order parameter for the blue phases.