Junction, device and methods of fabrication

A Josephson junction comprising superconducting electrodes (20) interconnected via an intermediate Josephson barrier (22), wherein the superconducting electrodes (20) and the intermediate Josephson barrier (22) are made out of the same chemical elements and are in a pristine condition. The junction is made using a scanning electron beam in the presence of a precursor in an electron beam induced deposition process (EBID). The electrodes and barrier can differ from one another in one or more local material characteristics, e.g. a ratio of chemical element constituents, morphology or lattice order. The precursor can be Tungsten hexacarbonyl W(CO)6 which is used to deposit tungsten carbide WC superconducting wires