Abstract
The influence of oxygen content on the structural and magnetic properties of the layered Co-based perovskites PrBaCo2O5+δ (0.16<δ<0.80) was investigated by means of both X-ray diffraction and bulk magnetic measurements. An antiferromagnetic state is found for δ<0.35 compounds. For the samples with an oxygen stoichiometry δ=0.5, a strong competition between ferro- and antiferromagnetic states exists in a narrow temperature range 180<T<250K. For δ∈[0.35-0.7], the temperature and field dependencies of the magnetization measurements point toward the appearance of a cluster-glass, in which oxygen-rich and oxygen-poor clusters coexist. The long-range ferromagnetic order, observed for larger oxygen contents (δ>0.7), could thus be arising from the percolation of oxygen-rich ferromagnetic clusters.
| Original language | English |
|---|---|
| Pages (from-to) | 1348-1350 |
| Number of pages | 3 |
| Journal | Physica B: Physics of Condensed Matter |
| Volume | 359-361 |
| Issue number | SPEC. ISS. |
| DOIs | |
| State | Published - Apr 30 2005 |
| Externally published | Yes |
Funding
The authors thank the Swiss National Science Foundation for financial support through grant 200021-100194 and NCCR MaNEP project. Financial support (project no. 278) by the INTAS is also gratefully acknowledged.
Keywords
- Cobalt oxides
- Magnetic phase transitions
- Spin-state transitions