Nonlocal signatures of hybridization between quantum dot and Andreev bound state*

Andreev bound states (ABS) in semiconductor-superconductor hybrid structures have attracted considerable attention in the past decade.
We present a novel device geometry based on a semiconducting InAs two-dimensional electron gas proximitized by superconducting Al. The device allows for tunneling spectroscopy at the ends of a gate-defined nanowire with a grounded parent superconductor.
Preliminary results from a 600 nm long nanowire show that ABS can be induced and controlled in the nanowire by electrostatic gating. The bound states appear correlated at both ends of the nanowire in tunneling spectroscopy. To further demonstrate the high level of control, the ABS in the nanowire is brought on resonance with a local quantum-dot level. The effect of the resulting hybridization on the bound state is observed at the other end of the nanowire, which strongly indicates that we are indeed measuring an extended quantum state at two separate locations.