Wetting Transition and Divergence of the Extrapolation Length near the Nematic-Isotropic Transition

We report an investigation of the wetting behavior of 5CB drops on silicon wafers. Nematic drops exhibit a characteristic mesoscopic thickness that diverges as the nematic-isotropic transition is approached. This divergence may be associated with the vanishing of the anchoring strength, or equivalently, to a wetting transition occurring near the nematic-isotropic transition. Pretransitional effects due to the structuring of the drop close to the solid surface can be observed in the isotropic phase.