RQMP (CPM) Seminar

>Hund Metals: Strong Electronic Correlations Beyond the Mott Paradigm

Antoine Georges

Flatiron Institute

Multi-band/multi-orbital materials such as transition-metal oxides, iron superconductors or twisted bilayer systems offer a fertile platform for exploring the physics of strong electronic correlations. In this context, the interplay of the Hubbard U with Hund’s rule and spin-orbit coupling, as well as orbital differentiation, lead to rich physics beyond the paradigmatic ‘Mottness’. In recent years, the concept of ‘Hund metals’ has emerged and has successfully explained the properties of iron superconductors and ruthenates. In this talk, I will focus especially on Sr₂RuO₄ – an amazing material which can serve as a precision laboratory for many-body physics. I will report on recent high-resolution ARPES experiments which allow to put Dynamical Mean-Field Theory (DMFT) framework to a direct test. I will review how DMFT provides a conceptual and computational framework to understand Hund metals.