Dielectric method for determining the electrical critical field in ferroelectric liquid crystals

A. Levstik , Z. Kutnjak , B. Zeks , S. Dumrongrattana , C. Huang

Both the electrical field and the dielectric constant (ε0 ΔεG) associated with the Goldstone mode in the ferroelectric liquid crystals are related to the helical pitch. A direct relation between these two physical quantities is established. We have calculated the electrical critical field for both DOBAMBC and DOBA-1-MPC compound from the measured temperature variation of ε0 ΔεG and polarization without any adjustable parameter. Just below the transition temperature region, the results obtained agree qualitatively with the experimental data. Away from the transition temperature, there exist systematic deviations.

Domaines: Articles anciens

A. Levstik, Z. Kutnjak, B. Zeks, S. Dumrongrattana, C. Huang. Dielectric method for determining the electrical critical field in ferroelectric liquid crystals. Journal de Physique II, 1991, 1 (7), pp.797-803. ⟨10.1051/jp2:1991110⟩. ⟨jpa-00247556⟩