Shift of the semimetal-dielectric phase transition boundary in case of violation of sublattice symmetry in the extended Hubbard model

Abstract

Within the framework of the extended Hubbard model on a hexagonal lattice, the effect of sublattice symmetry breaking on the position of the semimetal-antiferromagnet phase transition is studied. The study is carried out using the Quantum Monte Carlo method with five auxiliary Hubbard fields. It is shown that the difference in the intensity of the on-site interaction of electrons on the sublattices leads to a shift of the phase transition point towards lower values of the interaction parameter. An antiferromagnetic condensate is considered.