EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Strongly-correlated materials are sometimes defined as systems, where standard formulations of density functional theory do not work any more for a proper description of the electronic properties. We will show in this talk how to incorporate strong correlations in ab-initio calculations via the dynamical mean-field theory. This combination, coined DFT+DMFT, allows to describe Mott insulators and other strongly-correlated materials such as Pnictide superconductors or Ruthenates.

As a concrete example, we will discuss the emergence of unconventionally strong magnetism in correlated systems. Starting from the bulk material SrTcO3, we will highlight the importance of the Mott insulating state for a high transition temperature. We will extend this theory to low-dimensional systems such as Manganite-Titanate heterostructures and the single-layer magnet CoBr2. The fact that these materials are close to a metal-insulator transition will be key to explain the strong magnetism, and opens a door for further technological improvements of magnetic systems.