Competition between electroconvection and Fréedericksz distortions in nematic liquid crystals with slightly positive dielectric anisotropy

Planar electroconvection in nematic liquid crystals with positive dielectric anisotropy is theoretically studied in the nonlinear regime. The system is characterized by a competition between the nonequilibrium electroconvection instability and the equilibrium Fréedericksz distortions. Near a resulting multicritical bifurcation point a splay-roll instability and a bistability between the convective and the homogeneous states occur.