Quantum transport in in-plane hybrid InSb-Al nanowire networks

Strong spin-orbit semiconductor nanowires with induced superconductivity are predicted to host Majorana zero modes (MZMs). Exchange (braiding) operations of MZMs form the logical gates on topological qubits and require a network of nanowires. Here, we demonstrate essential quantum transport properties on our novel in-plane selective-area growth InSb-Al platform which allows complex semiconductor-superconductor nanowire networks. The quantum transport phenomena include phase-coherent transport up to 5 harmonics of Aharonov-Bohm oscillations with a phase coherence length of ~10 μm. Tunneling spectroscopy on in-plane hybrid InSb/Al nanowires demonstrates a hard superconducting gap, accompanied by distinct oscillations of Andreev bound states while increasing the magnetic field. A Cooper pair island integrated in the nanowire network shows 2e-periodic Coulomb oscillations. The results confirm the high quality of the InSb nanowire networks, holding great promise for this platform for scalable topological networks.