Instability patterns in ultrathin nematic films: Comparison between theory and experiment
Laboratoire de Physique Statistique, Ecole Normale Supérieure, UPMC Univ Paris 06, Université Paris Diderot, CNRS - 24 rue Lhomond, 75005 Paris, France, EU
Accepted: 27 September 2010
Motivated by recent experimental observations (Delabre U. et al., Langmuir, 24 (2008) 3998), we reconsider an instability of ultrathin nematic films, spread on liquid substrates. Within a continuum elastic theory of liquid crystals, in the harmonic approximation, we find an analytical expressions for the critical thickness as well as for the critical wave number, characterizing the onset of instability towards the stripe phase. Comparing theoretical predictions with experimental observations, we establish the utility of surface-like term such as an azimuthal anchoring.
PACS: 61.30.Hn – Surface phenomena: alignment, anchoring, anchoring transitions, surface-induced layering, surface-induced ordering, wetting, prewetting transitions, and wetting transitions / 61.30.Dk – Continuum models and theories of liquid crystal structure / 64.70.M- – Transitions in liquid crystals
© EPLA, 2010