Regensburg 2004 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

MA: Magnetismus

MA 16: Magn. Kopplungsph
änomene

MA 16.3: Vortrag

Mittwoch, 10. März 2004, 15:45–16:00, H22

Evidence for three-dimensional non-collinear antiferromagnetic order in single-crystalline FeMn ultrathin films — •W. Kuch, L. I. Chelaru, F. Offi, J. Wang, M. Kotsugi, and J. Kirschner — Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle

Experimental evidence for a three-dimensional non-collinear antiferromagnetic spin structure in ultrathin single-crystalline fcc Fe₅₀Mn₅₀ layers is obtained from magnetic circular dichroism photoelectron emission microscopy (XMCD-PEEM) and x-ray magnetic linear dichroism. Layer-resolved as-grown domain images of epitaxial trilayers grown on Cu(001) are presented in which FeMn is sandwiched between ferromagnetic layers with different easy axes. Measurements of trilayers using Co or Ni as the bottom layer, and combinations of Co and Ni as top layer reveal the simultaneous presence of antiferromagnetic spin components in the film plane and normal to the film plane. The absence of x-ray magnetic linear dichroism at the Fe L₃ absorption edge in FeMn/Co bilayers points towards an FeMn spin structure with no collinear order in the film plane even when in contact with a saturated ferromagnetic layer. This result has important implications on theoretical models of the magnetic interface coupling between ferromagnetic and antiferromagnetic layers and for understanding the exchange bias effect along different magnetization components.