The relation between the crystal structure and superconductivity has been investigated for La2-xBixCuO4+δ with excess oxygen, in which the phase separation observed in La2CuO4+δ is suppressed. In the range of 0.03≲δ≲0.1 and T≲100 K, the crystal structure is orthorhombic for x = 0.05, while it is tetragonal for x=0.10. With increasing δ, Tc increases and then reaches the maximum value, 20-25 K, at δ ≳ 0.05 for 0.05≤x≤0.10, independent of the crystal structure. The overall symmetry of the crystal structure is concluded not to be so responsible for the appearance of high-Tc superconductivity.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering