Dirac-fermions and conductance-oscillations in (s,d)-wave superconductor/normal graphene junctions

We investigate quantum transport in a normal/superconductor graphene heterostructure, including the possibility of an anisotropic pairing potential in the superconducting region. We find that under certain circumstances, the conductance displays an undamped, oscillatory behaviour as a function of applied bias voltage. Also, we investigate how the conductance spectra are affected by a d-wave pairing symmetry. These results combine unusual features of the electronic structure of graphene with the unconventional pairing symmetry found for instance in high-T_c superconductors.