FIB-deposited carbon-based superconducting nanowires with Tc ˜ 7 K

Abstract

AbstractWe have fabricated carbon-containing nanowires by a gallium focused ion beam-induced deposition process from the precursor phenanthrene, C14H10. The electrical conductivity of the nanowires is only weakly temperature dependent below 300K, and reveals a superconducting state below Tc ˜ 7 K. We have measured the temperature dependence of the resistive upper critical field Hc2(T), and from those data, estimate the zero temperature critical field and coherence length to be 8.8 T and 6.1 nm, respectively. The Tc of this material is approximately 40% higher than that in any other FIB/direct write nanowire, such as those based on W(Ga), and thus offers the possibility of fabricating superconducting direct-write nanostructures that function at liquid helium temperature.