Seminarium Fizyki Materii Skondensowanej

The study of strong correlation in model Hamiltonians has produced a varied palette of results which promise exciting applications for material design. Still, bridging the computational description of simple models with realistic _ab initio_ Hamiltonians presents outstanding challenges, particularly with respect to the accurate yet affordable approximation of multi-orbital models. In this talk, I will give a bird's eye view on our recent efforts to push on some of these numerical issues, which draw inspiration from traditional techniques from the computational chemistry community. In particular, I will discuss the use of simple (and some less simple) variants of selected Configuration Interaction (sCI) to efficiently compute one-body Green functions, with direct application as impurity solvers in Hamiltonian-based DMFT. We will go over the basic heuristic of the algorithm, briefly visit a couple of representative applications in solid state and chemical physics, as well as an honest portrayal of the challenges it faces and how one may alleviate them. For the meeting link contact Pawel Jakubczyk.