A computational approach to the optical Freedericksz transition

The optical Freedericksz transition in a homeotropic nematic liquid crystal cell is modeled using a solver which combines direct solution of Maxwell’s equations with a relaxation algorithm for the liquid crystal director. We find that even in the equal elastic constant case the continuous optical Freedericksz transition can be driven first order. For films in which the optical retardation of the extraordinary wave is sufficiently large, a whole set of discontinuous jumps in transmission coefficient can occur. These jumps correspond to the existence of optical resonances in the liquid crystal film. Our results agree in the short wavelength limit with paraxial approximation calculations, and provide a strong test of the FDTD method for anisotropic materials such as liquid crystals.