Local and non-local spectroscopy of phase-biased Josephson junctions in an InSbAs two-dimensional electron gas

Planar Josephson junctions (JJs) have been proposed as a route to creating phase-controllable Majorana zero-modes. We study such devices in a hybrid InSbAs/Al two-dimensional electron gas, which has previously shown promising electrical properties for the realization of topological superconductivity (i.e., strong spin-orbit coupling, a large g-factor and clean superconductor-semiconductor interfaces). Using simultaneous tunnelling spectroscopy at both ends of the junction, we observe Andreev bound states whose energies are modulated by the phase. The three-terminal nature of these devices also allows us to study the non-local conductance, giving additional insights into the bulk of the JJ. At finite in-plane magnetic fields, we see the onset of a phase-dependent inversion in the sign of the non-local conductance and the emergence of zero-bias peaks in local spectroscopy.