Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Atomic and Electronic Structure of the Fe₃O₄ (111)/MgO(111) Model Polar Oxide Interface

Journal Article · · Physical Review. B, Condensed Matter
High resolution transmission electron microscopy (HRTEM) and density functional calculations are used to study the effect of interface polarity on the atomic and electronic structure of the prototype Fe?O?(111)/MgO(111) polar oxide interface. We show that atomically abrupt interfaces exist between the MgO(111)-substrate and magnetite(111) film in regions separated by Fe nanocrystals, and propose a solution for this oxide-oxide interface structure. Comparisons of through-focus/through-thickness experimental HRTEM images with calculated images for model interface structures suggest metal-oxygen-metal (i.e., Mg-O-Fe) interface bonding with octahedral (B) coordination of the first Fe monolayer, rather than the combination of tetrahedral-octahedral-tetrahedral (ABA) stacking also found in Fe?O?. First-principles calculations for all the different models find metal-induced gap states in the interface oxygen layer. Consistent with the HRTEM results, the MgO-Fe?O? interface stacking Mg/O/Mg/O/3FeB/O/FeAFeBFeA? is calculated to be the energetically most favorable, and effectively screening the MgO(111) substrate surface polarity. The data and calculations exclude mixing of Mg and Fe across the interface, in contrast to the commonly invoked mechanism of cation mixing at compound semiconductor polar interfaces.
Research Organization:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC05-76RL01830
OSTI ID:
876921
Report Number(s):
PNNL-SA-45276; 13290; KP1303000
Journal Information:
Physical Review. B, Condensed Matter, Journal Name: Physical Review. B, Condensed Matter Journal Issue: 19 Vol. 72
Country of Publication:
United States
Language:
English

Similar Records

Atomic and electronic structure of the Fe3O4(111) / MgO(111) model polar oxide interface
Journal Article · Mon Oct 31 23:00:00 EST 2005 · Physical Review. B, Condensed Matter and Materials Physics · OSTI ID:1152575

Selected Growth of Cubic and Hexagonal GaN Epitaxial Films on Polar MgO(111)
Journal Article · Fri Jun 03 00:00:00 EDT 2005 · Physical Review Letters · OSTI ID:20696343

Atomic and electronic structure of polar Fe 2 O 3 (0001)/MgO(111) interfaces
Journal Article · Sun Jul 01 00:00:00 EDT 2012 · Physical Review. B, Condensed Matter and Materials Physics · OSTI ID:1051019