Magnetoresistance oscillations in superconducting granular niobium nitride nanowires

We report on magnetoresistance oscillations in superconducting NbN _x nanowires synthesized through ammonia gas annealing of NbSe ₃ recursor nanostructures. Even though the transverse dimensions of the nanowires are much larger than the superconducting coherence length, the voltage-current characteristics of these nanowires at low temperatures are reminiscent of one-dimensional superconductors where quantum phase slips are associated with the origin of dissipation. We show that both the magnetoresistance oscillations and voltagecurrent characteristics observed in this work result from the granular structure of our nanowires.