The magnetic behavior of Na-, K-, Rb-doped YBCO ceramic samples is investigated at ac magnetic field at 77 K. For small Rb and Na concentrations, an increase of the field-dependent component of the critical current is observed. High dopant concentrations lead to deterioration of the critical parameters of the YBCO material. The results are interpreted as due to 'soiling' of the intergranular boundary by the dopant impurities and Cu excess.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics