Quantization and Confinement Effects in Superconducting Films with an Antidot Lattice

Abstract
We have studied flux line confinement by regular arrays of submicron holes (triangular and square antidot lattices) in superconducting films. Critical current density j c and pinning force f p are very strongly enhanced due to pinning of single or multi-quanta vortices by the antidots. Direct measurements of j c and f p for several well-defined antidot diameters D, proves that pinning centers with size considerably larger than the temperature-dependent coherence length ξ(T) are much more efficient than those with D\congξ(T).