▎ 摘　　要

We investigate effects of the filled Dirac sea on the SU(4) symmetry breaking for the integer quantum Hall states of graphene with long-ranged electrostatic Coulomb interactions. Our model also includes Hubbard and nearest-neighbor repulsive interactions with strengths U and V, respectively. We find the symmetry breaking of n = 0 Landau level is accompanied by an SU(4) polarization of the filled Dirac sea. We compute the phase diagram for filling factor v = 0,+/- 1 in the U-V space at magnetic fields relevant to experiments. The Dirac sea polarization significantly influences the phase diagram. It suppresses the Kekule ordering at v = 0 and induces it at v = +/- 1. We also calculate the excitation gaps at small tilted magnetic fields. This enables us to conclude that the ground state is a charge density wave at v = 0 and valley-spin polarized at v = +/- 1. We delineate a region in the U-V space consistent with the experiments.