Superconducting films with antidot arrays -Novel behavior of the critical currentG. R. Berdiyorov, M. V. Milosevic and F. M. Peeters
Departement Fysica, Universiteit Antwerpen Groenenborgerlaan 171, B-2020 Antwerpen, Belgium
received 16 January 2006; accepted in final form 3 March 2006
published online 29 March 2006
Novel behavior of the critical current density jc of a regularly perforated superconducting film is found, as a function of applied magnetic field H. Previously pronounced peaks of jc at matching fields were always found to decrease with increasing H. Here we found a reversal of this behavior for particular geometrical parameters of the antidot lattice and/or temperature. This new phenomenon is due to a strong "caging" of interstitial vortices between the pinned ones. We show that this vortex-vortex interaction can be further tailored by an appropriate choice of the superconducting material, described by the Ginzburg-Landau parameter . In effective type-I samples we predict that the peaks in jc(H) at the matching fields are transformed into a step-like behavior.
74.25.Sv - Critical currents.
74.78.-w - Superconducting films and low-dimensional structures.
74.25.-q - Properties of type I and type II superconductors.
© EDP Sciences 2006