A method and an optical device for bistable storage of optical information, together with reading and erasure of the optical information, using a photoactivated shift in a field dependent phase transition between a metastable or a bias-stabilized ferroelectric (FE) phase and a stable antiferroelectric (AFE) phase in an lead lanthanum zirconate titanate (PLZT). An optical disk (1) contains the PLZT. Writing and erasing of optical information can be accomplished by a light beam (14) normal to the disk (1). Reading of optical information can be accomplished by a light beam (5) at an incidence angle of 15 to 60 degrees to the normal of the disk (1).