Effect of surface treatment on pattern formation of topological defects in nematic liquid crystals

Abstract

It is well-known that the averaged molecular orientation of nematic liquid crystals can be controlled by the surface. On the other hand, the effect of thickness of the alignment layer is not understood thoroughly. Here we experimentally realize the homeotropic alignment on polydimethylsiloxane surface using UV/ozone treatment. We demonstrate that preparing a surface which ensures both the director orientation and the electrical insulation enables to induce the regular pattern formation of topological defects.