SEMINAR @ SISSSA, prof. P. Biscari 16/05/07 at 16.00 hrs.

[Barbara Corzani]

Prof. Paolo Biscari
Politecnico di Milano

Titolo: "Liquid crystalline order on curved surfaces"

Wed 16 May 2007 at 16.00 hrs. room B


Abstract:

We study the interaction between a nematic liquid crystal and a
curved surface.
In the first part of the talk we study the coupling between the local
curvature tensor of a hosting membrane and the local 2D nematic order
parameter of an embedded liquid crystal. We study the shape instabilities
induced by the nematic order and how the curved geometry modifies the
stability of nematic point defects.
In the second part of the talk we consider a 3D nematic liquid crystal
bounded by a rough surface. The wrinkling of the surface induces a
partial melting in a thin boundary layer. In the bulk, the roughness effect
is equivalent to an effective anchoring potential, whose characteristic
parameters can be derived from the microscopic roughness parameters.

References:
P. Biscari, E.M. Terentjev: Nematic membranes: Shape instabilities of
closed achiral vesicles. Phys. Rev. E 73, 051706 (2006)
P. Biscari, S. Turzi: Boundary-roughness effects in nematic liquid 
crystals.
SIAM J. Appl. Math. 6, 447-463 (2007)

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