Magnetoresistance oscillations in superconducting granular niobium nitride nanowires

Abstract

We report on magnetoresistance oscillations in superconducting ${\text{NbN}}_{x}$ nanowires synthesized through ammonia gas annealing of ${\text{NbSe}}_{3}$ precursor 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 voltage-current characteristics observed in this work result from the granular structure of our nanowires.