ИСТИНА

We report on the fabrication and measurements of submicron Josephson junctions formed by Cu nanowires coupled to superconducting planar Nb terminals. Cu nanowires consisted of single crystalline blocks were obtained by templated electrochemical deposition using anodic alumina as a porous matrix. The superconducting characteristics of our samples as the functions of temperature and magnetic field have been studied. Josephson supercurrent values up to Ic = 30 µA were found, with copper nanowire weak link resistivity Rwl ≈ 0.4 Ω and ρwl ≈ 1 µΩ cm at 1.2K. Through the use of Nb as a superconductor, the Josephson coupling persists at temperatures up to 3.5 K. In all junctions the critical current monotonously decreases with the magnetic field, it can be explained by a recently developed theoretical model for the proximity effect in ultrasmall Josephson junctions. Our studies demonstrate the feasibility of the application of such Josephson junction in the superconducting electronics as a submicron weak link.