Magnetic-field-induced isotropic-nematic phase transition in porous media Original Research Article

In the framework of the random anisotropy nematic spin model we investigate the influence of an external magnetic ordering field on the properties of isotropic-nematic phase transition in porous media. Depending on the values of relative randomness three types of phase diagrams are predicted. In the relative low randomness régime the magnetic field dramatically changes the phase diagram due to possibility of existence of two speronematic phases. At relative intermediary and large randomness the influence of the ordering field is only to increase the speronematic-paranematic phase transition temperature and to diminish the strength of the transition.