Mechanisms of flexoelectric switching in a zenithally bistable nematic device

Flexoelectric effects in nematic liquid crystals are well known to occur through combinations of either the sum or the difference of the splay and bend polarizations. In this work we examine the role of both mechanisms in the switching of zenithally bistable nematic devices, and conclude that both can cause bistable switching. Interestingly, we find that the most important flexoelectric coefficient in terms of reducing the switching threshold voltage can be either the splay or bend coefficient, depending purely on the relative dielectric permittivities of the grating and liquid crystal materials. © 2009 American Institute of Physics. DOI: 10.1063/1.3153971