Flexoelectric
domains
Flexoelectric domains are an electric field induced
pattern characterized by spatially periodic equilibrium director distortions.
They are observable by polarizing microscope in some planar nematic liquid
crystals at DC or at very low frequency AC driving as stripes running parallel
to the initial director. Its interpretation was first given by a simplified
(one-elastic-constant approximation) model by Bobylev and Pikin, which provided
the threshold voltages and wave numbers as well as a condition of existence (a
relation between the flexoelectric coefficients and other material
parameters).
Flexoelectric domains in the calamitic nematic Phase 5. |
Flexoelectric domains in the banana nematic ClPbis10BB. |
Our
group has been investigating flexoelectric domains experimentally in various
nematics, in close co-operation with theoreticians at the Institute of Physics,
University of Bayreuth, Bayreuth, Gernany.