Width and temperature dependence of hysteretic current–voltage character in long Niobium microbridges

We report a study of the switching behavior in the current–voltage characteristics of long (∼8 μm) Nb microbridges in the hysteretic regime. Microbridges of various widths, ranging from .71μm to 3.7μm, were prepared via standard optical lithography and reactive plasma etching techniques and the switching behavior was studied in a temperature range of 0.8Tc⩽T⩽Tc. The current driven switching from superconducting to normal state of the bridge was analyzed in the Ginzburg–Landau formalism while the resistive-to-superconducting switching was analyzed using the hotspot model.