Ground-State Superfluid Phase Diagram of the Two-Dimensional Fermionic Hubbard Model with Next-Nearest-Neighbour Hopping

In this work, we employ the Bold Diagrammatic Monte Carlo method to establish the superfluid phase diagram in terms of density and interaction strength and for several values of next-nearest-neighbour hopping. We find that although a multitude of superfluid states persists up to moderate interactions the picture changes severely compared to the weak-coupling interaction limit. We investigate into how relative proximity to the Van Hove filling affects superfluid order parameters and find that this effect diminishes with increasing interaction strength.