Nonlocal conductance spectroscopy of Andreev bound states in gate-defined InAs/Al nanowires

The charge character of Andreev bound states (ABSs) in a three-terminal semiconductor-superconductor hybrid nanowire was measured using local and nonlocal tunneling spectroscopy. The device is fabricated using an epitaxial InAs/Al two-dimensional heterostructure with several gate-defined side probes. ABSs give rise to distinct local and nonlocal conductance signatures which evolve as a function of magnetic field and gate voltage. At high magnetic fields, ABSs are found to oscillate around zero as a function of gate voltage, with modifications of their charge consistent with expectations for the total Bardeen-Cooper-Schrieffer charge of ABSs.

Automated summary

The charge character of Andreev bound states (ABSs) in a three-terminal semiconductor-superconductor hybrid nanowire was measured using local and nonlocal tunneling spectroscopy. The ABSs exhibited distinct local and nonlocal conductance signatures, which changed with magnetic field and gate voltage. At high magnetic fields, the charge of ABSs oscillated around zero as a function of gate voltage, consistent with the total Bardeen-Cooper-Schrieffer charge of ABSs.