Complete phase diagram of rare-earth nickelates from first-principles

Abstract

Complex oxides: Simulating the complete phase diagram of nickelates A new theoretical approach provides a complete phase diagram of rare-earth nickelates, reproducing the key features seen in experiments. Transition metal oxides with a pervoskite crystal structure exhibit a broad range of behaviours due to a complex the interplay between lattice, electronic and magnetic degrees of freedom. Rare-earth nickelates are a particularly interesting class of perovskite oxide that undergo a highly tunable (and potentially exploitable) metal-insulator transition. Theoretically describing the insulating phase of nickelates, however, is far from trivial and two seemingly distinct descriptions have emerged. A team of researchers led by Manuel Bibes at Unité Mixte de Physique CNRS/Thales use first-principles simulations to somewhat reconcile these conflicting visions, fully describing the electronic and magnetic ground state of nickelates, as well as hinting at strategies for tuning these fascinating materials.