Superconducting quantum Hall systems have been proposed as an approach to realizing non-Abelian quasiparticles [1], motivating graphene–superconductor experiments that reported signatures of crossed Andreev reflection in fractional quantum Hall states, mainly using single-layer graphene [2]. Bilayer graphene provides a complementary system with a gate-tunable band structure in the quantum Hall state. In bilayer graphene, Andreev reflection has been reported in NbN junctions [3], while experiments with other superconducting contacts remain limited. We study a superconductor/bilayer graphene junction using MoGe with a superconducting transition temperature of ~7 K and a high critical field of ~10 T. At zero-field we have observed the Andreev reflection as shown in Fig. 1. The dip structure of the differential conductance indicates that, while it detects the signal from the superconductor, the spectrum is dominated by the normal reflection. The fitting by Blonder-Tinkham-Klapwijk leads to a barrier strength parameter Z of ~4. Extending this approach to crossed Andreev reflection and holds potential for realizing non-Abelian quasiparticles in bilayer graphene based superconducting quantum Hall systems theoretically proposed [1].

1. D. J. Clarke et al., Nat. Commun. 4, 1348 (2013) DOI: 10.1038/ncomms2340
2. Ö. Gül et al., Phys. Rev. X 12, 021057 (2022) DOI: 10.1103/PhysRevX.12.021057
3. D. Wang et al., Nano Lett. 21, 8229 (2021) DOI: acs.nanolett.1c02020