Site preference of the partially substituted 3d metal M and superconducting and magnetic properties have been investigated for Pb2Sr2Y1 - xCax(Cu1 - yMy)3O8 (M = Fe, Co, Ni, Zn, Ga). It has been found from powder neutron diffraction that Fe atoms preferentially occupy the Cu(1) site in the oxygen-free Cu layer, while Co, Ni, Zn and Ga atoms occupy the Cu(2) site in the CuO2 layer. From correlation between this site preference of M and the superconducting and magnetic properties, it has been concluded that the partial Cu(1)-site substitution shows little effect on the superconductivity and that there remains antiferromagnetic correlation between Cu2+ spins in the Cu(2) site in the normal state even for the high-Tc samples of x = 0.5 with Tc ≈ 80 K.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering