Regular Article

Study of the orientational ordering in the field-induced intermedate phase from the SmC *Fi₂ phase in chiral smectic liquid crystals

Université Tunis El-Manar, Faculté des Sciences de Tunis, Laboratoire de physique de la matière molle et de modélisation électromagnétique (LP3ME), Campus Universitaire Farhat Hached, 2092 Tunis, Tunisia

^* e-mail: hassen.dhaouadi@ipeit.rnu.tn

Received: 3 June 2019
Received in final form: 23 July 2019
Accepted: 9 August 2019
Published online: 13 September 2019

Abstract

Under an electric field, chiral smectic liquid crystals transit usually to the unwound SmC* phase where the helical structure is completely unrolled. Sometimes the sample transits initially towards an intermediate polar state before the total destruction of the helix. The discovery of this intermediate phase opens a promising field of application especially in the field of color displays. This gives importance to the study and the characterization of this new phase. Based on the extension of the Hammaneh-Taylor model (H&T model), a theoretical study of these field-induced phase transitions was carried out. Two hypotheses of the dynamics that give rise appearance of the intermediate phase have been discussed. Numerical analysis confirms the known experimental results; the intermediate phase has a three-layer periodicity structure.