High interfacial exchange energy in TbFeCo exchange-bias films.

The exchange-bias films of ferrimagnetic/ferrimagnetic, ferromagnetic/ferromagnetic, and ferromagnetic/antiferromagnetic bilayers were fabricated to investigate their interfacial exchange energy Δσ. Δσ of TbFeCo bilayers is larger than 5 erg/cm[SUP2]at room temperature. By varying the composition of TbFeCo layers, both positive and negative exchange bias have been observed. A highly uncompensated-spin interface model was proposed to explain the strong exchange interaction in TbFeCo bilayers. Due to the characteristics of highly uncompensated-spin interface at TbFeCo bilayers, the exchange coupling field in TbFeCo bilayers exhibited less dependence on interfacial roughness than that in IrMn/NiFe bilayers. In addition, by adjusting the composition of TbFeCo, the anisotropy of pinning layer can be manipulated and exhibits strong effects on exchange bias of TbFeCo bilayers. [ABSTRACT FROM AUTHOR]