Plateau borders of smectic liquid crystalline films

Abstract

We investigate the geometrical properties of Plateau borders in an arrangement of connected smectic A free standing films. The geometry is chosen such that a circular Plateau border surrounds a planar smectic film and connects it with two smectic catenoids. It is demonstrated that, similar to soap films, the smectic film geometry can be described by a negative line tension of the circular contact region. Thus, the equilibrium angle between the films depends upon the liquid content in this region, and with increasing liquid content, deviations from Plateau's rule are observed. The experimental results are qualitatively comparable to soap films. A possible origin of slight quantitative differences is discussed.

Keywords:

• foams
• Plateau border
• Plateau's rules
• decoration lemma
• thin films
• smectic liquid crystals

Acknowledgements

The authors thank Marvin Weyland for participating in some of the experiments and DFG for financial support within Project STA 425/20. RA acknowledges support by the DAAD. We thank D. Weaire for useful comments.