Eur. Phys. J. B 37, 19-24 (2004)
https://doi.org/10.1140/epjb/e2004-00026-0

Dynamic regimes in films with a periodic array of antidots

Nanoscale Superconductivity and Magnetism Group, Laboratory for Solid State Physics and Magnetism K.U. Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium

Corresponding author: ^a alejandro.silhanek@fys.kuleuven.ac.be

Received: 13 October 2003
Published online: 19 February 2004

Abstract

We have studied the dynamic response of Pb thin films with a square array of antidots by means of ac susceptibility measurements. At low enough ac drive amplitudes h, vortices moving inside the pinning potential give rise to a frequency- and h-independent response together with a scarce dissipation. For higher amplitudes, the average distance travelled by vortices surpasses the pinning range and a critical state develops. We found that the boundary between these regimes smoothly decreases as T increases whereas a step-like behavior is observed as a function of field. We demonstrate that these steps in arise from sharp changes in the pinning strength corresponding to different vortex configurations. For a wide set of data at several fields and temperatures in the critical state regime, we show that the scaling laws based on the simple Bean model are satisfied.