Transport properties through wide and short ballistic graphene junctions are
studied in the presence of arbitrary dopings and magnetic fields. No dependence
on the magnetic field is observed at the Dirac point for any current cumulant,
just as in a classical diffusive system, both in normal-graphene-normal and
normal-graphene-superconductor junctions. This pseudo-diffusive regime is
however extremely fragile respect to doping at finite fields. We identify the
crossovers to a field-suppressed and a normal ballistic transport regime in the
magnetic field - doping parameter space, and provide a physical interpretation
of the phase diagram. Remarkably, pseudo-diffusive transport is recovered away
from the Dirac point in resonance with Landau levels at high magnetic fields.Comment: 4+ pages, 2 figures. Minor corrections. Published version