Biaxial nematic order induced by smectic fluctuations

摘要

We report on a series of measurements on the microscopic structure and the magneto-optical properties of ancalamitic liquid crystalline compound in its nematic phase. Structural studies show the existence of short-range,ntilted smectic order consistent with pretransitional effects above an underlying smectic phase. Concomitantly,nmagneto-optical results exhibit the existence of an optic axis not collinear with the uniaxial director. Thisnapparent biaxial nature is discussed within the context of coupling between the tensor nematic and the smecticnorder parameters.