Magnetic anisotropy of textured CrO2 thin films investigated by X-ray magnetic circular dichroism

• Published in: Applied physics. A, Materials science & processing Vol. 74; no. 6; pp. 747 - 753
• Main Authors: GOERING, E, JUSTEN, M, GEISSLER, J, RÜDIGER, U, RABE, M, GÜNTHERODT, G, SCHÜTZ, G
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.06.2002
• Subjects: Aluminum oxide; Chromium oxides; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Deposition; Dichroism; Equivalence; Exact sciences and technology; Magnetic properties and materials; Magnetic properties of monolayers and thin films; Magnetic properties of surface, thin films and multilayers; Orientation; Physics; Thin films; X-rays; Thin films; CVD; Inorganic compounds; Magnetic dipoles; Magnetic anisotropy; Chromium oxides; Transition element compounds; Magnetic circular dichroism; X-ray spectra; Experimental study; Texture
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s003390201302

Highly a-axis-textured CrO2 films have been deposited on Al2O3 (0001) substrates by chemical vapor deposition. CrO2 has been found to have highly a-axis (010)-oriented columnar growth on a Cr2O3 (0001) initial layer. The six-fold surface symmetry of the Cr2O3 initial layer leads to three equivalent in-plane orientations of the a-axis-oriented CrO2 unit cell. We report Cr L2,3 X-ray magnetic circular dichroism data along the surface normal and at 60 off-normal sample orientation. For a 60 sample alignment, a strong increase of the projected orbital moment could be observed for unoccupied majority t2g states using moment analysis. Therefore, the c axis is identified as the intrinsic magnetic easy axis of CrO2. In addition, a small spin moment and a very strong magnetic dipole term Tz have been found.