2020 Volume 63 Issue 9 Pages 459-464
Layerwise antiferromagnetically-coupled bct-Mn(001) ultra-thin monolayer films grown on bcc-Fe(001) at 370 K have been studied as an ideal interface between ferromagnet and antiferromagnet with the Néel temperature much higher than room temperature, which is the key issue to understand exchange bias in magneto resistance junctions. Also, the Mn(001) films on Fe(001) have been used as one of standard samples to examine spin-polarized scanning tunneling microscopy (SP-STM) measurements. Here, we demonstrated how the interface roughness between ferromagnet and antiferromagnet changes magnetic structures of the films. SP-STM magnetic imaging was performed on Mn(001) films grown on an Fe(001)-whisker at 470 K in ultrahigh vacuum. Although magnetic images showed the layerwise antiferromagnetic coupling between layers, additional magnetic structures were found, namely 3-nm-size 180° magnetic domains due to interface intermixing and non-collinear magnetic coupling areas due to a dense interface step density.
