High-pressure sintering and structural study of Nd1.85Ce0.15CuO4−y superconductor

✍ Scribed by Yingfan Xu; Changqin Jin; Zhenhong Mai; Guangzhao Pan; Daoyang Dai; Yushu Yao; Wenkui Wang

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 815 KB
• Volume: 204
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(93)91010-s

✦ Synopsis

Electron-doped

Nd1.8jCe0,,5Cu04_y superconductors sintered under high pressures and ambient pressure have been investigated by means of resistivity measurements, X-ray diffraction, scanning electron microscopy and high-resolution transmission electron microscopy. The results show that the samples are composed of a near single tetragonal T' phase. The lattice parameters of the T' phase increase slightly with the increase of pressure. Lattice distortions and a high density of plane-defects were observed in the high-pressure samples, while few defects were present in the ambient pressure one. The pressure has a positive effect on the r,. The sample with the highest T, value was treated under a pressure of 4.0 GPa and a temperature of 803 K. The role of pressure in the reduction of Nd,.ssCeo,,sCuO+, is explained by the removal of oxygen defects and the enhancement of electron density in the CuOt planes.