Towards carbon nanotube growth into superconducting microwave resonator geometries

The in-place growth of suspended carbon nanotubes facilitates the observation of both unperturbed electronic transport spectra and high-Q vibrational modes. For complex structures integrating, e.g., superconducting rf elements on-chip, selection of a chemically and physically resistant material that survives the chemical vapor deposition (CVD) process provides a challenge. We demonstrate the implementation of molybdenum-rhenium coplanar waveguide resonators that exhibit clear resonant behavior at cryogenic temperatures even after having been exposed to nanotube growth conditions. The properties of the MoRe devices before and after CVD are compared to a reference niobium device. (a) Schematic of the CVD growth environment; a metal thin film is exposed to a CH4 /H-2 atmosphere at 850 degrees C. (b) MoRe coplanar waveguides still display superconductivity after this treatment, with clear resonant behavior of a /4 structure.