Magnetic exchange at realistic CoO/Ni interfaces
Physical Science & Engineering Division, KAUST, 23955-6900 Thuwal, Kingdom of Saudi Arabia
Received: 3 February 2012
Received in final form: 1 June 2012
Published online: 30 July 2012
We study the CoO/Ni interface by first principles calculations. Because the lattice mismatch is large, a realistic description requires a huge supercell. We investigate two interface configurations: in interface 1 the coupling between the Ni and Co atoms is mediated by O, whereas in interface 2 the Ni and Co atoms are in direct contact. We find that the magnetization (including the orbital moment) in interface 1 has a similar value as in bulk Ni but opposite sign, while in interface 2 it grows by 164%. The obtained magnetic moments can be explained by the local atomic environments. In addition, we find effects of charge transfer between the interface atoms. The Co 3d local density of states of interface 2 exhibits surprisingly small deviations from the corresponding bulk result, although the first coordination sphere is no longer octahedral.
Key words: Solid State and Materials
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2012