Changes in the Thermal Stability of 2G HTS Wires by Local Modification of the Stabilization Layer

In order to use 2G HTS wires in superconducting devices, it is important to understand the origin of thermal instabilities in these materials. Previous results showed that inhomogeneities in the critical current distribution are not the only factor that determines the heat generation distribution along the sample when the current exceeds the critical value. In this work, different types of controlled defects have been generated in the Cu-layer using laser ablation. In all cases, laser parameters have been chosen while assuring that the critical current of the superconductor does not deteriorate. It has been obtained that even if the thickness of the stabilizing layer is reduced from 20 mu m to less than 10 mu m in some regions, the sample response to overcurrents is not modified.