Semiconductor nanowire-based superconducting qubits

K.D. Petersson, T.W. Larsen, L. Casparis, M. Olsen, F. Kuemmeth, T.S. Jespersen, P. Krogstrup, J. Nygård, and C.M. Marcus

Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark

Superconducting transmon qubits are a promising basis for a scalable quantum information processor. The recent development of semiconductor InAs nanowires with molecular beam epitaxy-grown Al contacts presents new possibilities for building hybrid superconductor/semiconductor devices using precise bottom up fabrication techniques. Here, we take advantage of these high quality materials to develop gate-tunable transmons with semiconductor nanowire weak link Josephson junctions. Strong coupling to a transmission line microwave cavity and coherent qubit control via gate voltage pulses are demonstrated and, for the first devices, we measure coherence times up to ~2.5 μs. Our gate-tunable nanowire transmons may enable new means of control for large-scale qubit architectures and hybrid topological quantum computing schemes.