Planar nematic anchoring due to a periodic surface potential

摘要

A polyimide-coated substrate is rubbed periodically with the stylus of an atomic-force microscope. The effective polar and azimuthal anchoring strength coefficients for planar anchoring are determined as a function of the spatial separation L of rub lines. Both anchoring coefficients are found to decrease monotonically with L, apparently leveling off at nonzero values for L greater than or similar to2 mum. The observed behavior is discussed in terms of a combination of intrinsic anchoring strength in the rubbed regions and a surface memory effect. (C) 2001 American Institute of Physics. References: 24