Research Papers in Physics and Astronomy


Date of this Version

December 1993


Published by Am Physical Soc. Phys. Rev. B 48 (1993) 15812-15816. Copyright 1993. Permission to use.


Exchange hardening of nanostructured two-phase systems composed of an aligned hard phase and a soft phase with high magnetization is investigated using an approach which yields analytic nucleation fields from the micromagnetic vector equation, and accounts for interactions between the soft regions. In suitable structures the nucleation field is proportional to the volume-averaged anisotropy constant. For example, a multilayer composed of alternating 2.4 nm hard-magnetic Sm2Fe17N3 layers and 9 nm Fe65Co35 layers can have an energy product as high as 1 MJ/m3 (120 MG Oe), with a rare-earth content of only 5 wt %. Giant energy products may also be achieved in suitable cellular and disordered structures.

Included in

Physics Commons