Layer Thinning in Freely-Suspended Thin Liquid Films of a Symmetric Liquid Crystal Dimer
ORAL
Abstract
We report optical reflectivity and dynamic light scattering (DLS) studies on freely suspended smectic films of a symmetric liquid crystal dimer, which exhibits the phase sequence isotropic---nematic---twist-bend nematic---smectic in cooling. In sufficiently thin films the reflectivity $R$ is expected to scale as the square of the number of smectic layers ($N^{\mathrm{2}})$ while the frequency $f$ of underdamped layer fluctuations scales as $N^{\mathrm{-1/2}}$. On heating thin films drawn in the smectic phase, we observe a sequence of layer thinning transitions, with $R$ and $f$ following the expected scaling relations, provided the stepwise melting involves double rather than single layers. We will describe a model to explain the unusual layer thinning process.$\backslash $pardWe thank M. G. Tamba and G. Mehl for providing the liquid crystal compound: NSF grant DMR-1307674.
–