Flexoelectric Effect in Biaxial Nematics

Abstract

The exoelectric eect provides a linear coupling between electric polarization and orientational deformation in liquid crystals. It inuences many electrooptical phenomena and it is used in some bistable nematic devices. A statistical theory of dipole exoelectric polarization in biaxial nematic liquid crystals is used to calculate temperature dependence of order parameters, elastic constants, and exoelectric coecients. The splitting of the two Meyer exoelectric coecients and the appearance of new exoelectric coecients is obtained at the uniaxial-biaxial nematic transition. The ordering of the split exoelectric coecients corresponds to the ordering of the split elastic constants.

Photosensitive Bent-Core Liquid Crystals with Laterally Substituted Azobenzene Unit

“…According to their structure, they can form various mesophases with unique properties in comparison with other classes of LCs [19][20][21]. Bent-core nematics (BCN) can have biaxial character [22][23][24][25][26] and exhibit a huge flexoelectric effect compared to conventional calamitic nematics [27][28][29][30], which predetermines them for new generation of optoelectrical devices, holographic media [31,32], photonics and optical data storage [33,34]. In this study, we focused on a group of BCLCs possessing the azo group in one of the elongating side arms.…”