Abstract
Iron oxide films were produced using ion-beam-assisted deposition, and Raman spectroscopy and x-ray diffraction indicate single-phase magnetite. However, incorporation of significant fractions of argon in the films from ion bombardment is evident from chemical analysis, and Fe/O ratios are lower than expected from pure magnetite, suggesting greater than normal disorder. Low temperature magnetometry and first-order reversal curve measurements show strong exchange bias, which likely arises from defects at grain boundaries, possibly amorphous, creating frustrated spins. Since these samples contain grains ∼6 nm, a large fraction of the material consists of grain boundaries, where spins are highly disordered and reverse independently with external field.
Original language | English (US) |
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Article number | 173902 |
Journal | Journal of Applied Physics |
Volume | 116 |
Issue number | 17 |
DOIs | |
State | Published - Nov 7 2014 |
Externally published | Yes |
ASJC Scopus subject areas
- Physics and Astronomy(all)