Influence of bond orientational order on the switching time of ferroelectric smectics

Abstract

We report studies of the bulk switching time as a function of temperature in the chiral smectic C (C^∗ ) and chiral smectic I (I^∗) phases of 4-(2-methylbutyl) phenyl 4'-(octyloxy)-(1,1')-biphenyl-4-carboxylate (8OSI) which shows a continuous evolution from the fluid C^∗ to the hexatic I^∗ phase. The thermal variation of the switching time is found (to our knowledge for the first time) to scale remarkably well with the hexatic order parameter for the two phases determined experimentally by Brock et al for 8OSI, the racemic form of 8OSI. Similar correlation is observed in the case of 8SI^∗, the alkyl analog of 8OSI^∗, which shows a first order C^∗-I^∗ transition.