2025/05/20 by Tharathep Plienbumrung, J.M. Moree, Plienbumrung, Tharathep +5 · 1 citation
Physics and Astronomy · Materials Science · #Theoretical and Computational Physics #Magnetic and transport properties of perovskites and related materials #Advanced Thermodynamics and Statistical Mechanics
paper · pdf · doi:10.48550/arxiv.2505.14276
We present an effective two-band model for infinite-layer nickelates NdNiO2 that consisting of a d band centered at Ni site and an interstitial s-like band centered at Nd site. To the large extent of the wave functions, we find intersite Coulomb interactions to be substantial. We then use the variational cluster approach together with mean-field theory to investigate magnetic and charge ordering. While tendencies towards charge modulation are found, they are weak and might be due to finite-size effects. Magnetic order is determined mostly by the filling of the d band and hardly affected by including longer-ranged interactions. For a d-band density consistent with density-functional theory, magnetic ordering vanishes once quantum fluctuations are included to a sufficient spatial extent. Apart from self-doping, d and s bands remain largely uncoupled despite the presence of inter-orbital Coulomb interaction and (small) inter-orbital hopping.