Superconducting flux qubits with pi-junctions = Supraleitende Flussqubits mit pi-Kontakten

In this thesis, we present a fabrication technology of Al/AlOx/Al Josephson junctions on Nb pads. The described technology gives the possibility of combining a variety of Nb-based superconducting circuits, like pi-junction phase-shifters with sub-micron Al/AlOx/Al junctions. Using this approach, we fabricated hybrid Nb/Al flux qubits with and without the SFS-junctions and studied dispersive magnetic field response of these qubits as well as their spectroscopy characteristics