Tunable supercurrent diodes with spectral flow of Andreev bound state

Supercurrent diode effects have attracted interest recently to shed light on materials and device properties, and also to enable new technologies relevant to Quantum Information Sciences. In this talk, we will present the supercurrent diode effect in chiral carbon nanotubes with an applied magnetic field aligned along the tube. We find that in carbon nanotube-based Josephson junctions, a magnetic field threading the tube induces spectral flow in the Andreev bound state spectrum. The supercurrent diode effect is shown to have a large diode efficiency under moderate magnetic field strengths and a magnetically-tunable anomalous phase associated with an orbital mechanism rather than the usual inverse Edelstein effect. Furthermore, we show the diode polarity can be switched by tuning the nanotube's doping. We elucidate the origin of the diode effect's gate tunability as due to a spectral flow between Andreev bound states and supercurrent-carrying states in the continuum.