Influence of an electric field on phase transitions in ferroelectric liquid crystals
Titel:
Influence of an electric field on phase transitions in ferroelectric liquid crystals
Auteur:
Bahr, Ch. Heppke, G. Sabaschus, B.
Verschenen in:
Liquid crystals
Paginering:
Jaargang 11 (1992) nr. 1 pagina's 41-48
Jaar:
1992-01-01
Inhoud:
The transition temperatures between various smectic liquid crystal phases in chiral (ferroelectric) compounds have been determined as a function of an applied DC electric field. We find that SG-SA and SG-SC transitions show a field-induced temperature shift proportional to the applied field strength similar to the already known behaviour of first order SC-SA transitions. In contrast, for the nonferroelectric SB-SA and SE-SB transitions no effect of the electric field is observed. The field-induced temperature shift is compared with the temperature shift occurring in chiral-racemic systems of the same compounds (see Bahr, Ch., Heppke, G., and Sabaschus, B., 1991, Liq. Crystals, 9, 31). Using Landau theory we derive a simple relation between these two quantities.