Structure and magnetism of nanocrystalline and epitaxial (Mn,Zn,Fe)3O4 thin films
Abstract
Nanocrystalline (NC) textured Mn0.5Zn0.6Fe1.9O4 (MZFO) films, grown at room temperature on both isostructural and non-isostructural substrates, show magnetization values significantly suppressed from epitaxial MZFO films. X-ray absorption spectroscopy and x-ray magnetic circular dichroism measurements indicate larger ratios of Fe3+ to Fe2+ ions on the tetrahedral sites in the NC films compared to the epitaxial films. The magnetization loops of the NC films are shifted by 200−400 Oe at low temperatures. No such effect is observed in the epitaxial films. We hypothesize that the presence of a more structurally disordered, possibly magnetically frustrated, matrix exchange biases the crystalline regions.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 21, 2012
- Source ID
- 10.1063/1.3676619
Entities
People
- A. J. Grutter
- E. Arenholz
- F. J. Wong
- J. M. Iwata-harms
- U. S. Alaan
- V. V. Mehta
- Y. Suzuki
Organizations
- Lawrence Berkeley National Laboratory
- Office of Naval Research
- University of California, Berkeley