Coercivity mechanism and long-range coupling of anisotropic Nd-Dy-Fe-Co-B/Fe composite thick film

In the present work, the long-range coupling between soft- and hard-magnetic layers and a dual enhancement of coercivity and polarization are achieved in anisotropic Nd-Dy-Fe-Co-B/Fe composite thick film with Ta spacer layers. It has been found that the coercivity mechanism dominated by the pinning mechanism is enhanced with increasing the periodic number of multilayers. The effect of the Ta spacer layer isolating the hard-magnetic phase grains leads to an increase in the coercivity. Continuous irreversible distribution confirms the coherent reversal of the soft and hard magnetic phases. The increase of polarization is caused by the dipole interactions acting in the long-range coupling between the layers.