Effect of electron–electron interaction on 2D multimode Peierls state in the presence of anisotropy

The effect of electron–electron (e–e) interaction on the 2D Peierls state in the presence of anisotropy is numerically studied using the Peierls–Hubbard model with a half-filled electronic band, within the Hartree–Fock approximation. It is shown that, in a certain region of the e–e interaction strength, the antiferromagnetic spin-density wave (SDW) can coexist with the bond-order wave with the nesting vector, which is absent in the isotropic case. The anisotropic multimode Peierls distortions are found insensitive to weak e–e interaction, while the SDW state is the ground state for strong e–e interaction.