Characterizing the Exchange Interaction of Sm-Co/Co (and Fe65Co35) Magnetic Films

Exchange interaction plays an important role on magnetic properties of nanocomposite magnets consisting of hard- and soft-magnetic phases. Here the exchange interaction in the Sm-Co/Co (and Fe65Co35) magnetic films was characterized by measuring static (m(r)(H)) and demagnetized (m(d)(H)) remanence curves. According to conventional method: delta m(H)=m(d)(H) - [1 - 2m(r)(H)], the exchange interaction was evaluated. The switching fields H-p(1) and H-p, at which static (m(r)(H)) and demagnetized (m(d)(H)) remanence show the fastest change, were identified. The relative ratio eta=H-p-H-p(1)/H-p of switching fields Hp' and Hp has a linear relationship with the maximum value of delta m(H) curves, proposing an alternative way to characterize the exchange interaction.