Fabrication and Characterization of Nanoscale Periodic Ferromagnetic Structures on Superconducting Thin Films

This research investigates the transport properties of ferromagnetic nanostructures made by nickel or cobalt on superconducting thin films. The superconducting thin films were covered by an insulating layer, and the periodic ferromagnetic nanostructures were fabricated on top of the insulating layer. On separate superconducting thin films, periodic ferromagnetic nanostructures were embedded into the thin films. The photolithography method was used to make contact pads for a four-probe measurement. In order to fabricate the magnetic nanostructures, an Electron Beam Lithography (EBL) system was utilized. The nanoscale patterns were filled with ferromagnetic materials by using a thermal evaporating method or an electroplating technique. The superconducting properties were measured at low temperature (2.0 K<T<8.0 K) for low temperature superconductors and at high temperature (85.0 K<T