EXCHANGE BIASING IN MBE GROWN FE3O4 COO BILAYERS - THE ANTIFERROMAGNETIC LAYER THICKNESS DEPENDENCE/

Exchange biasing has been studied for a series of [100] and [111] orie nted, epitaxial Fe3O4/CoO bilayers grown by oxidic MBE. The low-temper ature exchange biasing versus CoO layer thickness is compared to theor etical models for exchange biasing. We argue that the Malozemoff rando m field model does not apply to this system. The exchange biasing calc ulated according to the Meiklejohn-Bean model, assuming nearest-neighb or exchange coupling across a flat and magnetically uncompensated inte rface, differs for [100] oriented bilayers by a factor of similar or e qual to 8 from the experimental value. (C) 1996 American Institute of Physics.