STABILITY OF MAGNETIC-FIELD-INDUCED DIPOLAR ORDER IN A FERROELECTRIC SIDE-CHAIN LIQUID-CRYSTAL POLYMER

The stability of in-layer dipolar order in a side-chain ferroelectric liquid crystalline polymer has been investigated by probing the optica l birefringence produced by aligning the mesogenic side groups with a high magnetic field. The temperature dependence of the decay time asso ciated with the mesogen relaxation from a state of saturated alignment obeys an Arrhenius law, with an activation energy two to three times higher than the typical value for low molecular weight liquid crystals . The exponent characterizing the relaxation process is found to be te mperature-dependent in the ferroelectric smectic-C phase, and approac hes unity near the polymer glass transition. The implications of these results for nonlinear-optics applications are discussed. (C) 1994 Ame rican Institute of Physics.