KRAMER-PESCH EFFECT AND DAMPING OF THE VORTEX MOTION IN THE CUPRATE SUPERCONDUCTORS

Kramer and Pesch discussed the fact that in the clean limit the radius of a vortex core in a type-II superconductor decreases proportionally to T with decreasing temperature. This ''Kramer-Pesch effect'' result s from the thermal population of the quasiparticle bound states in the vortex core. In addition to the case of a static vortex, this effect also has important consequences for the vortex dynamics. Because of th is, for the cuprate superconductors features of the damping of the vor tex motion are expected at low temperatures. We discuss recent measure ments of the electric resistance at high vortex velocities and of the microwave power absorption for different cuprate superconductors in co njunction with the Kramer-Pesch effect.