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Updated: Jul 19, 2026
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
c-director relaxation around a vortex of strength +1 in free-standing smectic-C films
A Eremin1, Ch Bohley, R Stannarius
1Institut für Experimentelle Physik, Otto-von-Guericke-Universität, Universitätsplatz 2, D-39106, Magdeburg, Germany. alexey.eremin@physik.uni-magdeburg.de
Abstract:
The relaxation of director fields in freely suspended smectic films is studied experimentally by means of polarizing microscopy, and analyzed by solving the torque balance equation under appropriate initial and boundary conditions. We consider in particular the role of anchoring conditions of the c-director at particles and defects in the film. The structure of regular relaxation patterns allows to determine the elastic anisotropy of smectic materials. The splay elastic constant can exceed the bend constant by a factor of two and more. A remarkable consequence of this anisotropy is the stick-slip-like relaxation around a central defect of topological strength s = + 1.
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