Critical behaviour of the dielectric constant for the smectic AC* transition under the electric field in ferroelectric liquid crystals

Date

2012-01-01

Author

Yurtseven, Hasan Hamit

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The temperature dependencies of the dielectric constant and the tilt angle (order parameter) are calculated under the electric field for the smectic A-smectic C* (AC*) transition in 4-(3-methyl-2-chlorobutanoyloxy)-4'-heptyloxybiphenyl (A7). The dielectric constant is fitted to the experimental data by using our mean field model with the biquadratic coupling between the spontaneous polarisation P and the tilt angle theta. Our results show that the mean field model with the P-2 theta(2) coupling describes satisfactorily the observed behaviour of the AC* transition in A7. It is indicated here that a first-order AC* transition occurring at low electric fields changes its character towards a second order as the electric field increases in A7.

Subject Keywords

Dielectric constant, Order parameter

URI

https://hdl.handle.net/11511/39439

Journal

PHYSICS AND CHEMISTRY OF LIQUIDS

DOI

https://doi.org/10.1080/00319104.2011.651209

Collections

Department of Physics, Article

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Citation Formats

H. H. Yurtseven, “Critical behaviour of the dielectric constant for the smectic AC* transition under the electric field in ferroelectric liquid crystals,” PHYSICS AND CHEMISTRY OF LIQUIDS, pp. 367–377, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39439.