SURFACE-PLASMON RESONANCE IMAGING OF LIQUID-CRYSTAL ANCHORING ON PATTERNED SELF-ASSEMBLED MONOLAYERS

The anchoring of the nematic liquid crystal (LC) 4'-n-octyl-4-cyanobip henyl (8CB) at derivatized self-assembled monolayer (SAM) surfaces has been investigated using surface plasmon resonance (SPR) microscopy. S urfaces having distinct areas (patterns) covered by different omega-fu nctionalized groups, one (-CF3) promoting homeotropic anchoring of the nematic director and the other (-OH) planar anchoring, were fabricate d from photopatterned SAMs. Our results show that SPR microscopy, whic h is sensitive to the alignment on the mesoscale (i.e., within 300 nm of the interface) can be used to spatially resolve the anchoring of ad sorbed LC films, with a lateral resolution on the order of a few micro meters, as a function of temperature. In addition, we observe surface melting of the crystalline phase at the SAM boundary by both homeotrop ic and planar aligned melts.