Superconducting Ruddlesden-Popper nickelates from first-principles

The nascent field of nickelate superconductivity -- originally motivated by analogies to the cuprates -- has been revitalized by the recent discovery of superconductivity in octahedrally coordinated Ruddlesden-Popper nickelates, including both bilayer and trilayer architectures, where superconductivity emerges under applied pressure and compressive strain. These findings establish a new family of materials for exploring unconventional, electronically mediated high-temperature superconductivity. We will discuss our recent progress in understanding the electronic structure evolution of the bilayer Ruddlesden-Popper nickelate La₃Ni₂O₇ as a function of pressure and strain, as well as its counterpart La₅Ni₃O₁₁. We will present ongoing work combining many-body perturbation theory with dynamical mean-field theory (GW+EDMFT)—a fully first-principles framework—aimed at revealing new insights into the many-body electronic structure of these systems. Finally, we will highlight the discovery of new family of nickelates realized through topotatic oxidation, emphasizing this method as a powerful synthetic route to access metastable phases of layered oxides.