Superconductivity near two-dimensional Van Hove singularities: a determinant quantum Monte Carlo study
This study used determinant quantum Monte Carlo simulations to find how superconductivity ($T_c$) in a two-dimensional attractive Hubbard model is affected by Van Hove singularities (VHS) in the electronic density of states. It found that near a VHS, $T_c$ is enhanced for weak to intermediate interactions. However, this enhancement disappears when interactions become strong, and the maximum $T_c$ occurs at an intermediate interaction strength away from the VHS density.