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Updated: Aug 1, 2026

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Impurity-assisted interlayer exchange coupling across a tunnel barrier
M Ye Zhuravlev1, E Y Tsymbal, A V Vedyayev
1Department of Physics and Astronomy, Center for Materials Research and Analysis, University of Nebraska, Lincoln, Nebraska 68588, USA.
Abstract:
Localized impurity or defect states in the insulating barrier layer separating two ferromagnetic films affect dramatically the interlayer exchange coupling (IEC), making it significantly stronger compared to perfect barriers. We demonstrate that the impurity-assisted IEC becomes antiferromagnetic if the energy of the impurity states matches the Fermi energy and that the coupling strength decreases with temperature. These results explain available experimental data on the IEC across tunnel barriers.
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