Field-induced optical biaxiality in chiral smectic-A liquid crystals

Observation of field-induced optical biaxiality in a chiral smectic-A Liquid crystal is reported for the first time. Optical transmission measurements as a function of electric field demonstrate that a material exhibiting a large electroclinic effect also exhibits a pronounced optical biaxiality. It is shown that the biaxiality is correlated with the electroclinic tilt angle and its field dependence can be qualitatively explained in terms of a simple molecular model involving reorientation about the long molecular axis.