PEEM Imaging of Antiferromagnetic and Ferromagnetic Domains
Abstract
Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy coupled with polarization dependence is a powerful tool for the investigation of magnetic materials. Ferromagnetic materials are studied using the X-Ray Magnetic Circular Dichroism (XMCD) effect and antiferromagnetic materials are studied using the X-Ray Magnetic Linear Dichroism (XMLD) effect. Photoemission Electron Microscopy (PEEM) combines the capabilities of x-ray absorption spectroscopy with high resolution imaging. XMCD and XMLD can be used as contrast mechanisms in PEEM allowing the investigation of ferromagnetic and antiferromagnetic surfaces and domain structures with a spatial resolution of about 50 nm. The probing depth of NEXAFS and PEEM is given by the electron escape depth of about 2-10 nm. Therefore individual layers of multilayer structures can be studied independently due to the elemental specificity of the technique. We have studied the antiferromagnetic structure of surfaces of epitaxially grown NiO(100) and LaFeO3 (100) films and polycrystalline NiO films. The studies reveal that antiferromagnetic surfaces can have properties different from bulk properties. Effects we have observed include the reorientation of the antiferromagnetic axis at the surface, a reduced Néel temperature at surface defects, and a local reorientation of the antiferromagnetic axis in polycrystalline NiO induced by strain. Results on the interaction of the antiferromagnetic and ferromagnetic structure in multilayers will also be presented. note
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2000
- Bibcode:
- 2000APS..MARA24001A