A -site ordered perovskites Ca Cu3 Ge4 O12 and Ca Cu3 Sn4 O12, which are isostructural to antiferromagnetic Ca Cu3 Ti4 O12, were found to be ferromagnets. The special alignment of the Cu O4 planes in the perovskite structure plays an important role in the magnetic properties of Cu2+ spins. Direct exchange interaction gives rise to the ferromagnetic behavior in Ca Cu3 Ge4 O12 and Ca Cu3 Sn4 O12, whereas involvement of Ti-3d orbitals produces the antiferromagnetic superexchange interaction in Ca Cu3 Ti4 O12. This finding demonstrates that either ferromagnetic or antiferromagnetic behavior can appear within the same structural framework.
|ジャーナル||Physical Review B - Condensed Matter and Materials Physics|
|出版ステータス||Published - 2007 10 11|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics