Exchange-bias training effect in TbFe/ GdFe: Micromagnetic mechanism

Thomas Hauet (1) , S Mangin (1) , J Mccord (2) , F Montaigne (1) , Eric E. Fullerton (3)

1 IJL - Institut Jean Lamour
2 IFW Dresden - Leibniz Institute for Solid State and Materials Research
3 UC San Diego - University of California [San Diego]

We present magnetization and Kerr microscopy measurements of the exchange-bias training effect in hard/ soft, Tb 12 Fe 88 /Gd 40 Fe 60 , bilayers. These experimental results, compared with micromagnetic simulations, un-ambiguously show the role of the soft GdFe layer reversal on irreversible magnetic changes in the hard TbFe layer. After a partial reversal of the GdFe magnetization layer, the next field cycle exhibits a double hysteresis loop which is due to the existence of two types of domains in the sample, and only one of these domains has been subject to the training effect. The antiferromagnetically interfacial coupling and positive exchange-bias shift permit us to exclude any direct contribution from the magnetic field to this mechanism.

Mots clés: exchange-bias; amorphous; exchange-spring

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Thomas Hauet, S Mangin, J Mccord, F Montaigne, Eric E. Fullerton. Exchange-bias training effect in TbFe/ GdFe: Micromagnetic mechanism. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2007, 76, pp.144423. ⟨10.1103/PhysRevB.76.144423⟩. ⟨hal-01345098⟩