Electric Field Tunable Superconductor-semiconductor Coupling in Majorana Nanowires

Hybrid semiconductor nanowire-superconductor systems have attracted interest in recent years as possible platforms for hosting Majorana Zero Modes (MZM). Although this system has been extensively studied both theoretically and experimentally, it has recently become clear that the effective parameters of the system depend strongly on the electrostatic environment. We use InSb nanowires with epitaxially grown Al superconductor to study the effect of electrostatic gating on device parameters such as the superconducting gap and the effective g-factor. We find that the induced superconducting gap as well as the effective Zeeman g-factor changes as the device is tuned from strong coupling to weak coupling, which is corroborated by Schrödinger-Poisson simulations of the device geometry. We further investigate the effect this has on the phase diagram of Zero Bias Conductance Peaks (ZBCP), which are generally considered as a signature of MZM.