Ferronematics with soft particle anchoring in magnetic and laser fields

The influence of a magnetic field and an optical laser field on the orientational behavior of a ferronematic with positive magnetic and dielectric anisotropy is investigated. A slow transition from the homeotropic to the distorted alignment of the nematic director is found when the field strengths exceed certain threshold values. A correlation between the threshold values of the two fields is obtained and a phase diagram for this transition is determined. It is also found that in the presence of the two fields the distorted arrangement is more stable than the homeotropic one (its free energy per unit area is smaller).