Interfacial magnetic structure in Fe/NiO(001)

Using nuclear resonant scattering of synchrotron radiation and density functional theory calculations we have resolved the magnetic properties of the different Fe phases present at the Fe/NiO(001) interface, an epitaxial ferromagnetic/antiferromagnetic system. We have detected the presence of an interfacial antiferromagnetic FeO-like phase with a significantly increased magnetic moment compared to the case of a sharp interface. Already a few atomic layers above the interface, the Fe atoms have a bulk-like metallic character and the reversal of their magnetization is strongly influenced by the antiferromagnetic layer.

Figure 1

Sketches of the three model systems considered to simulate the Fe/NiO interface with (a) 0 FeO layers, (b) 1 FeO layer, and (c) 2 FeO layers. Small black circles (red): O, big gray circles (blue): Ni, and big, light gray circles (yellow): Fe.

Figure 2

NRS time spectra measured at selected values of the applied magnetic field $H$ along the decreasing-field branch of the hysteresis loop for (a) the IN sample and (b) the IF sample at RT. The topmost spectrum is acquired at $+200$ mT along the increasing-field branch of the loop. The magnetic field $H$ is applied collinear to the photon wave vector $\mathrm{k⃗}$. The fits of the spectra are also reported as a solid line.

Figure 3

Relative variation of the magnetization, obtained from the fitting of the NRS time spectra, along an external magnetic field cycle, for the metallic components used for the fitting of the NRS time spectra of the IN and IF samples (component #1 in Table ). The magnetic field $H$ is applied collinear to the photon wave vector $\mathrm{k⃗}$ and to the Fe[100] orientation.