Large zero-bias peaks in InSb-Al hybrid semiconductor-superconductor nanowire devices

We report electron transport studies on InSb-Al hybrid semiconductor-superconductor nanowire devices. Tunnelling spectroscopy is used to measure the evolution of subgap states while varying magnetic field and voltages applied to various nearby gates. At magnetic fields between 0.7 and 0.9 T, the differential conductance contains large zero bias peaks (ZBPs) whose height reaches values on the order 2e2/h. We investigate these ZBPs for large ranges of gate voltages in different devices. We discuss possible interpretations in terms of disorder-induced subgap states, Andreev bound states and Majorana zero modes.
Comment: This manuscript replaces "Quantized Majorana conductance" Nature 556, 74 (2018). Technical errors in Nature 556, 74 (2018) are corrected and the original claims now have a wider interpretation. A Retraction Note (in preparation) on Nature 556, 74 (2018) will include a detailed description of errors and the corrected data analyses