Superconducting properties of in-plane W-C nanowires grown by He focused ion beam induced deposition.

Focused ion beam induced deposition (FIBID) is a nanopatterning technique that uses a focused beam of charged ions to decompose a gaseous precursor. So far, the flexible patterning capabilities of FIBID have been widely exploited in the fabrication of superconducting nanostructures, using the W(CO) precursor mostly in combination with a focused beam of Ga ions. Here, the fabrication and characterization of superconducting in-plane tungsten-carbon (W-C) nanostructures by He FIBID of the W(CO) precursor is reported. A patterning resolution of 10 nm has been achieved, which is virtually unattainable for Ga FIBID. When the nanowires are patterned with widths of 20 nm and above, the deposited material is superconducting below 3.5-4 K. In addition, nanowires with widths of 60 and 90 nm have been found to sustain long-range controlled nonlocal superconducting vortex transfer along 3 μm. Overall, these findings strengthen the capabilities of He FIBID of W-C in the growth and patterning of in-plane superconducting nanodevices.