Self-organization of inclusions in free-standing filmsP. Cluzeau1, V. Bonnand1, G. Joly1, V. Dolganov2 and H.T. Nguyen3
1 Laboratoire de Dynamique et Structure des Matériaux Moléculaires, UMR CNRS 8024, Université de Lille I, 59655 Villeneuve d'Ascq, France
2 Institute of Solid State Physics, Russian Academy of Sciences, 142432, Chernogolovska, Moscow district, Russia
3 Centre de Recherche Paul Pascal, CNRS, Avenue A. Schweitzer, 33600 Pessac, France
(Received 1 July 2002 / Published online: 15 April 2003)
The behaviour of freely suspended smectic-C* ( ) films at the bulk -cholesteric ( ) phase transition has been investigated using polarized-reflected-light microscopy. Our experimental observations show that above the bulk - phase transition the order appears in different ways according to the film thickness. In thin films, the conventional layer-by-layer thinning occurs. In films of intermediate thickness inclusions nucleate inside the film. The distortions of the in-plane orientational order of the host phase induce elastic interactions between the inclusions and lead to their self-organization in chain-like structures. Both the dynamic of the chaining and the parameters driving the equilibrium distance between the inclusions in the chain are investigated. In thick films, fingers grow inside the film. The influence of the experimental conditions on the various processes is analysed.
64.70.Md - Transitions in liquid crystals.
61.30.Jf - Defects in liquid crystals.
61.30.Gd - Orientational order of liquid crystals; electric and magnetic field effects on order.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2003