ELASTIC CONSEQUENCES OF THE DIELECTRIC BEHAVIOR OF YBA2CU3O7-DELTA

Owing to the fact that superconductivity can be described as a dielectric phenomenon, where the screening of the repulsive electron-electron interaction is accounted for by introducing a temperature-dependent dielectric function epsilon(omega, k), in this paper emphasis is put on a brief discussion of values of epsilon consistent with high superconducting transition temperatures in principle as well as on experimental techniques which allow determination of the temperature-dependence of the dielectric function epsilon(omega, k).