The effects of electronic mechanisms for electron pairing in high temperature superconducting oxides on both the transition temperature Tc and the isotope effect parameter α are considered. It is shown that for the higher Tc oxides, measured values of Tc and α together with estimates of the phonon contributions are not consistent with high-frequency electronic mechanisms. Limitations of the theory and some constraints on low-frequency electronic mechanisms are also discussed.
Citation: Solid State Communications
Pub Type: Journals