Interface magnetism was investigated for Ir atoms in Mn73Ir 27/Co70Fe30 and Mn77Ir 23/Fe bilayers which showed an exchange bias effect. Scattering angle and X-ray energy dependent resonant X-ray magnetic scattering patterns were measured at a small angle region around the Ir L3 absorption edge to determine the induced magnetic structure of the Ir 5d magnetic moment. It is found that the induced Ir magnetic moment which follows applied field reversal is concentrated at the first atomic layer of the antiferromagnetic MnIr layer for both MnIr/CoFe and MnIr/Fe samples. The direction of the Ir moment is parallel to the magnetic moment of the ferromagnetic layer independent of the composition of the ferromagnetic layer. This behavior is different from that reported on the uncompensated 3d magnetic moment of Mn atoms. The average size of the Ir moment in the MnIr/CoFe bilayer is estimated to be about 1.4 times larger than that in the MnIr/Fe bilayer. These results are consistent with a first-principles band calculation.
- 5d magnetic moment of Ir
- Exchange bias effect
- Induced magnetic structure
- Interface magnetism
- Resonant X-ray magnetic scattering