We investigated the effect of a photovoltaic field generated on the surface
of iron-doped lithium niobate crystals on droplets of a ferroelectric nematic
liquid crystalline and a standard nematic liquid crystalline material deposited
on this surface. When such assembly is illuminated with a laser beam, a wide
range of dynamic phenomena are initiated. Droplets located outside the laser
spot are dragged in the direction of the illuminated area, while droplets
located inside the illuminated region tend to bridge each other and rearrange
into tendril-like structures. In the ferroelectric nematic phase (NF) these
processes take place via the formation of conical spikes evolving into jet
streams, similar to the behavior of droplets of conventional dielectric liquids
exposed to overcritical electric fields. However, in contrast to conventional
liquids, the jet streams of the NF phase exhibit profound branching. In the
nematic phase (N) of both the ferroelectric nematic and the standard nematic
material, dynamic processes occur via smooth-edged continuous features typical
for conventional liquids subjected to under-critical fields. The difference in
dynamic behavior is attributed to the large increase of dielectric permittivity
in the ferroelectric nematic phase with respect to the dielectric permittivity
of the nematic phase.Comment: 11 pages, 9 figure