▎ 摘　　要

A square graphene single electron transistor (SET) was defined with two side gates, and its transport was studied at low temperature at T = 2 K. At zero magnetic field, Coulomb blockade oscillations were clearly observed near the Dirac point of this device. At high magnetic field, in the quantum Hall regime, we observed ballistic tunneling of the carriers through the graphene SET, contrary to the Coulomb blockades observed while approaching the vicinity of the Dirac point.