Abstract
A series of infinite-layer compounds NdxSr1-xCuO2 were synthesized by high-pressure technique under different pressure, temperature, and time conditions. Crystal structure, microstructure, and superconducting properties of the samples obtained were systematically investigated as a function of the synthesis conditions. The stability of the IL phase was studied using annealing procedures in Ar- and O2-flow, as well as under oxygen pressure up to 90 bar followed by thermogravimetric, energy-dispersive X-ray analysis, and X-ray diffraction measurements. On the basis of the results obtained we suggest a decomposition mechanism for the infinite-layer phase, which is responsible for the degradation of Tc, as well as a routine to produce electron-doped infinite-layer compounds with a sharp diamagnetic signal of bulk superconductivity.
| Original language | English |
|---|---|
| Pages (from-to) | 145-152 |
| Number of pages | 8 |
| Journal | Journal of Superconductivity and Novel Magnetism |
| Volume | 13 |
| Issue number | 1 |
| State | Published - 2000 |
| Externally published | Yes |
Funding
The authors are indebted to A. Furrer for helpful discussions. A.P and A.M. thank the Geneva team for hospitality during their stay in Geneva. The authors are grateful to the Group of Crystallography, University of Geneva (K. Yvon, R. Cherny) for giving access to X-ray diffractometer and assistance in diffraction measurements. Sincere thanks are addressed to A. Naula for technical assistance in high-pressure synthesis. Financial support by the Swiss National Science Foundation (Project No. 7 IP 050162.96/1), Russian Foundation of Basic Research (Grant No. 96-02-16699), Russian State Scientific and Technical Research Programs ‘‘Neutron Investigation of Matter’’ (Project No. 96-104, 96-305) and ‘‘Superconductivity’’ (Project No. 96-051) is greatly appreciated.
Keywords
- Cu-O planes
- High pressure synthesis
- Infinitc-layar compounds
- Oxygen stoichiometry