Maria CHATZIELEFTHERIOU : Local and non-local electronic correlations: from toy models to realistic material simulations

Strongly correlated electronic systems exhibit intriguing properties and highly complex phase diagrams, including metal-to-insulator transitions, magnetic/charge orderings and the field’s holy grail: high temperature superconductivity. I will present results using state-of-the-art numerical techniques that allow for an accurate description of both strong local electronic correlations and spatial fluctuations in such systems.     I will first discuss the application of this approach on the study of a simple model, relevant for a series of materials, where we have analyzed the interplay of Mott physics and magnetic fluctuations [1]. We have identified the Slater and Heisenberg regimes in the phase diagram, which are separated by a crossover region of competing spatial and local electronic correlations. I will, moreover, present a work on the perovskite Sr2RuO4 compound, where we have performed realistic calculations and have accurately reproduced the experimentally estimated magnetic susceptibility – both its strength and its structure -, resolving a long-standing discrepancy between theory and experiment [2].

[1] M. Chatzieleftheriou, S. Biermann, E. Stepanov, PRL 132, 236504 (2024)
[2] M. Chatzieleftheriou, A. N. Rudenko, Y. Sidis, S. Biermann,  E. A. Stepanov, PRB 112 (19), 195118 (2025)