The superconducting transition temperature Tc and the position lifetime τ of YBa2Cu3O6.7, YBa2Cu3O7, Y2Ba4Cu7O15 and YBa2Cu4O8 have been determined under high pressures. The results demonstrate that all evolve from the same origin: two CuO5-pyramid layers with different transfers of electrons to their vicinity, which give rise to different Tc's at ambient pressure. This is consistent with our recent conjecture that all known cuprate high temperature superconductors are mere modifications of the 214 and 123 phases.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering