Spin reorientation at the antiferromagnetic NiO(001)

1
Spin reorientation at the antiferromagnetic
NiO(001) surface in response to an adjacent
ferromagnet
H. Ohldag, A. Scholl, F. Nolting, S. Anders, F.U.
Hillebrecht, and J. Stöhr
Exchange bias
Unidirectional anisotropy in FM adjacent to
AFM discovered 1956 by Meiklejohn and Bean
Exchange-bias field (size depends on many
parameters)

The exchange bias effect is exploited in magnetic
data storage devices, though the origin of this
effect is still poorly understood. Different
models do exist, most of them assume that the
magnetic structure at the surface is the same as
for the bulk.
Spin-flop
Interfacial spins
PEEM
Meiklejohn, Bean (1956) Takano et al. (1997)
Koon (1997)

• High Spatial Resolution
• Elemental Sensitivity
• Ferromagnetic Contrast
• Antiferromagnetic Contrast
• Surface/Interface Sensitivity

FM
AFM
step
grain / domain boundary