  The ability to localize and manipulate individual quasiparticles in
mesoscopic structures is critical in experimental studies of quantum mechanics
and thermodynamics, and in potential quantum information devices, e.g., for
topological schemes of quantum computation. In strong magnetic field, the
quantum Hall edge modes can be confined around the circumference of a small
antidot, forming discrete energy levels that have a unique ability to localize
fractionally charged quasiparticles. Here, we demonstrate a Dirac fermion
quantum Hall antidot in graphene in the integer quantum Hall regime, where
charge transport characteristics can be adjusted through the coupling strength
between the contacts and the antidot, from Coulomb blockade dominated tunneling
under weak coupling to the effectively non-interacting resonant tunneling under
strong coupling. Both regimes are characterized by single -flux and -charge
oscillations in conductance persisting up to temperatures over 2 orders of
magnitude higher than previous reports in other material systems. Such graphene
quantum Hall antidots may serve as a promising platform for building and
studying novel quantum circuits for quantum simulation and computation.
