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The European Physical Journal E

, Volume 19, Issue 4, pp 441–452 | Cite as

Faceting and stability of smectic A droplets on a solid substrate

  • P. OswaldEmail author
  • L. Lejček
Regular Article

Abstract.

It is shown that a smectic A droplet deposited on a solid substrate treated for strong homeotropic anchoring is faceted at the top in spite of the fact that there are no steps at the free surface, but instead edge dislocations in the bulk. The radius of the facet and the full profile of the curved part of the droplet are determined as a function of the temperature in the vicinity of a nematic-smectic A phase transition. It is shown that the observed profiles do not correspond to the actual equilibrium shape, but to metastable configurations close to their point of marginal stability. In addition, we predict that the profiles must be different for a given temperature depending on whether the droplet has been heated or cooled down to reach this temperature. Finally, we discuss the problem of the formation of giant dislocations in big droplets (Grandjean terraces).

PACS.

68.03.Cd Surface tension and related phenomena 61.30.Hn Surface phenomena: alignment, anchoring, anchoring transitions, surface-induced layering, surface-induced ordering, wetting, prewetting transitions, and wetting transitions 61.30.Jf Defects in liquid crystals 

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Copyright information

© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2006

Authors and Affiliations

  1. 1.Laboratoire de PhysiqueEcole Normale Supérieure de LyonLyon cedex 07France
  2. 2.Institute of PhysicsCzech Academy of SciencesPrague 8Czech Republic

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