Electro-osmosis and flexo-electricity in the dowser texture

摘要

Due to its low symmetry, the long-lived pseudo-planar texture, dubbed the dowser texture, has a flexo-electric spontaneous polarisation P-fe. Being degenerated, the dowser texture is easily aligned by the electric torque Gamma = P-fe x E acting on P. The dowser texture can also be aligned by Poiseuille flows driven by electro-osmosis. The hydrodynamic torques due to the electro-osmotic flows are linear in E like the electrical one. It is shown that in 5CB the electro-osmotic flows can alter measurements of the flexo-electric polarisation.