2020   03   az   p.13-18 A.R. Imamaliev1, M.A. Ramazanov2, G.M. Bayramov2, Sh.A. Humbatov2,
The influence of size effect of BaTiO3 particles on dielectric properties of smectic a liquid crystals with negative dielectric anisotropy		  pdf 

ABSTRACT

In this paper, the influence of submicron (100 - 500 nm) ferroelectric BaTiO3 particles on the voltage-lumen characteristics of a homeotropic-planar transition (Fredericks transition) in smectic A liquid crystal with positive dielectric constant anisotropy was studied by the capacitance-voltage characteristics measuring of the electro-optical cell. It is shown that the addition of BaTiO3 particles at least 1,7 times reduces the threshold voltage of the Fredericks transition. The explanation of the obtained results based on the concept of a local field of polarized ferroelectric particles is given.

Keywords: smectic A liquid crystal, magnetoelectric particles, spontaneous polarization, dielectric anisotropy, dielectric permeability.
PACS: 77.84.Nh, 42.70.Df, 77.22.-d, 61.30.Gd, 61.30.-v, 64.70.M-, 78.15.+e, 83.80.Xz

DOI:-

Received: 15.10.2020

AUTHORS & AFFILIATIONS

1. Institute of Physics of Azerbaijan National Academy of Sciences, 131 H.Javid ave, Baku, AZ-1143
2. Baku State University, 23, Z.Khalilov st., AZ-1148
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