Local Dielectric Breakdown Path along c‐Axis Planar Boundaries in Cr2O3 Thin Films
Abstract
The 3D atomic structure of an interface‐stabilized planar boundary in the magnetoelectric Cr2O3 thin films is reported based on scanning transmission electron microscopy as a function of scattering angle. Local boundary electron energy loss spectroscopy shows a prepeak on the O–K edge arising from unoccupied O 2p states. Density functional theory calculations reproduce the images and spectra and show that the boundary has smaller bandgap than bulk Cr2O3, but does not interrupt the (0001) surface spin polarization and boundary magnetization. The reduced bandgap at the boundaries means they provide potential breakdown paths in Cr2O3 thin films. The same planar defect is predicted to occur in other epitaxial corundum film/substrate systems.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 10, 2017
- Source ID
- 10.1002/admi.201700172
Entities
People
- Ashutosh Rath
- Christian Binek
- Congli Sun
- Dane Morgan
- Jie Feng
- Michael Street
- Paul M. Voyles
- William Echtenkamp
- Zhewen Song
Organizations
- Defense Advanced Research Projects Agency
- University of Wisconsin–Madison