EXPERIMENTAL CONSTRAINTS ON SOME MECHANISMS FOR HIGH-TEMPERATURE SUPERCONDUCTIVITY

Since its discovery, many mechanisms have been suggested to explain the phenomenon of high-temperature superconductivity in oxides. We propose that experimental data, along with theoretical models, can place constraints on or exclude many of these mechanisms. The isotope shift-alpha, the transition temperature T(c), the ratio of the electronic-specific-heat jump to the normal-state specific heat DELTA-C/gamma T(c), and the superconducting gap ratio 2-DELTA/k(B)T(c) are considered. We find limits on the applicability of solely phonon-based and combined phonon-electronic mechanisms.