Light Enhanced Flexoelectric Polarization in Waveguiding Structures with a Smectic A Liquid Crystal (SALC) Layer

Abstract

Flexoelectricity exists in all materials including centrosymmetric ones, unlike piezoelectricity which can exist only in ferroelectric phases of non-centrosymmetric materials. Flexoelectric effect is related to the electromechanical coupling caused by the electric polarization and the strain gradient. In particular, the flexoelectric effect in nematic liquid crystals (NLC) and smectic A liquid crystals (SALC) has been widely investigated both theoretically and experimentally. We have shown theoretically that the light enhanced layer strain in an optical and plasmonic waveguides with a SALC core creates a high frequency electric field. The light induced flexoelectricity in SALC can be used in flexoelectro-optic LC devices that have been based until now on NLC and cholesteric LC (CLC).