Controlling Dendritic Flux Avalanches by Nanostructure of Superconducting Films

Laser Nanostructured Metasurfaces in Nb Superconducting Thin Films

“…In our case, the eventual systematic branching of the flux penetration paths towards the vertical direction adds a special feature, which is related to the surface patterning. A somewhat similar effect has been previously observed in superconducting films with artificial periodic pinning [34][35][36][37]. In short, the topography of the samples promotes the eventual flux channeling (in our case, along the orientation of the ripples).…”

“…8, relying on actual typical values of the physical parameters for our Nb films. In brief, as it has been emphasized by many authors [31][32][33]36,37,[44][45][46] and recently compiled in an extensive topical review [5], the smooth penetration in low-T c superconducting thin films (Nb in particular) is intrinsically hampered by magnetothermal instabilities. Detrimental flux avalanches are promoted by the concurrence of low temperatures and high values of the critical current density, and may eventually end up with a very significant decay of the superconducting properties, as for instance the magnetic moment of the sample.…”