Tipping the balance between ferromagnetism and charge density waves in monolayer VSe2

The field of two-dimensional ferromagnets has been reinvigorated by the discovery of monolayer VSe2, which is reported to be ferromagnetic with a Curie point higher than 330 K. While multiple studies have reported the observation of charge density waves in these systems, the ferromagnetic state of monolayer VSe2 remains highly debated. We hypothesize that ferromagnetism in monolayer VSe2 is driven by a Van Hove singularity at the Fermi level, while nested Fermi surface sheets drive the charge density waves. Based on this picture, we use first-principles calculations to investigate whether electron doping and pressure can tip the balance between these two competing states.