Hund's metallicity enhanced by a van Hove singularity in cubic perovskite systems

A van Hove singularity (VHS) often significantly amplifies the electronic instability of a crystalline solid, including correlation-induced phenomena such as Hund's metallicity. We perform systematic study on interplay between coupling and structures with VHS focusing construct simplified tight-binding model targeting cubic perovskite materials test effects utilizing dynamical mean-field theory an exact diagonalization solver. The quasiparticle weight low-frequency power exponent self-energy provide quantitative estimation metallicity over phase diagram. find to substantially enhance results here suggest range parameters through which can bring great synergy coupling.