Realization of microwave quantum circuits using hybrid superconducting-semiconducting nanowire Josephson elements

  1. G. de Lange,
  2. B. van Heck,
  3. A. Bruno,
  4. D. J. van Woerkom,
  5. A. Geresdi,
  6. S. R. Plissard,
  7. E. P. A. M. Bakkers,
  8. A. R. Akhmerov,
  9. and L. DiCarlo
We report the realization of quantum microwave circuits using hybrid superconductor-semiconductor Josephson elements comprised of InAs nanowires contacted by NbTiN. Capacitively-shunted
single elements behave as transmon qubits with electrically tunable transition frequencies. Two-element circuits also exhibit transmon-like behavior near zero applied flux, but behave as flux qubits at half the flux quantum, where non-sinusoidal current-phase relations in the elements produce a double-well Josephson potential. These hybrid Josephson elements are promising for applications requiring microwave superconducting circuits operating in magnetic field.