Surface-induced polarization at a chiral-nematic-substrate interface.

A chiral nematic liquid crystal that is tilted by an angle θi with respect to a substrate is subjected to an ac electric field at frequency ω. The nematic director is found to oscillate azimuthally about the normal to the liquid crystal substrate interface at frequency ω, indicating that a nonzero polarization perpendicular to the molecular tilt plane exists at the interface. The interfacial polarization, anchoring strength coefficient, and bulk viscosity are obtained by measurements of the oscillation amplitude as a function of ω . a Author for correspondence. Email [email protected] Typeset using REVTEX