Mechanically generated surface chirality: Control of chiral strength

A substrate coated with an achiral polyimide alignment layer was scribed with the stylus of an atomic force microscope having a line-to-line force profile F A F B F C F A F B F C ... . The strength of the resulting chiral surface was examined using the nematic liquid crystal electroclinic effect induced by the surface. The magnitude of the electroclinic effect was found to increase with increasing scribing force, which suggests a method for controlling the chiral strength. Additionally, the electroclinic magnitude divided by the rms surface roughness was approximately constant with scribing force, suggesting that the azimuthal anchoring strength coefficient is nearly independent of the scribing force.