Magnetic and electronic properties of Eu0.9Ca0.1BaCo2O5.5+δ with the variation of oxygen stoichiometry
Abstract
The effect of the oxygen content on the magnetic and transport properties of the ferromagnetic Eu0.9Ca0.1BaCo2O5.5+δ has been investigated. Unlike the increase in TC with calcium content, paradoxically the TC value decreases as the oxygen content increases, as observed in the undoped phase. Assuming the Kanamori-Goodenough rules apply to this very complex magnetic system, these experiments suggest that the Co3+ disproportionation into Co4+ and Co2+, plays an important role in the appearance of ferromagnetism. The magnetic phase separation scenario of ferromagnetic domains embedded in an antiferromagnetic matrix play an important role in the ferromagnetism of the calcium doped "112" cobaltites. All the samples covering a wide range of oxygen content, exhibit p-type conductivity.
- Publication:
-
Journal of Applied Physics
- Pub Date:
- May 2011
- DOI:
- 10.1063/1.3587235
- arXiv:
- arXiv:1010.1897
- Bibcode:
- 2011JAP...109i3916M
- Keywords:
-
- antiferromagnetic materials;
- barium compounds;
- calcium compounds;
- electrical conductivity;
- europium compounds;
- ferromagnetic materials;
- magnetic domains;
- magnetic transitions;
- 75.30.Kz;
- 75.50.Dd;
- 75.50.Ee;
- 75.60.Ch;
- 72.20.Fr;
- 72.80.Ga;
- Magnetic phase boundaries;
- Nonmetallic ferromagnetic materials;
- Antiferromagnetics;
- Domain walls and domain structure;
- Low-field transport and mobility;
- piezoresistance;
- Transition-metal compounds;
- Condensed Matter - Materials Science
- E-Print:
- 26 pages including figs