Competing exchange interactions in Co-doped ZnO: Departure from the superexchange picture
Competing exchange interactions in Co-doped ZnO: Departure from the superexchange picture
D'Ambrosio, S.; Pashchenko, V.; Mignot, J.; Ignatchik, O.; Kuzian, R.; Savoyant, A.; Golacki, Z.; Grasza, K.; Stepanov, A.
Abstract
We report the results of a comprehensive study of the exchange interactions in Co-doped ZnO using inelastic neutron scattering, electron paramagnetic resonance, and magnetic property measurements. In particular, we observe an unprecedentedly strong spatial anisotropy of the two nearest-neighbor exchanges, J((1)) = -25.6 +/- 0.3 K and J((2)) = -8.5 +/- 0.4 K, along with the distant-neighbor J values of ferromagnetic sign. We argue that the superexchange mechanism alone cannot account for the obtained data and we suggest that an additional mechanism leading to a strong ferromagnetic spin coupling is responsible for these findings. We also discuss the origin of this ferromagnetic mechanism.
Beteiligte Forschungsanlagen
- Hochfeld-Magnetlabor (HLD)
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Physical Review B 86(2012), 035202
DOI: 10.1103/PhysRevB.86.035202
Cited 16 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-18349