First-principle study of Sr-doping effect in Nd1-xSrxNiO2

Sr-doped infinite layer nickelate Nd1-xSrxNiO2 was recently reported as a superconductor analogous to the layered copper oxides. Previous works revealed that two bands of mainly Nd 5d and Ni 3d characters cross the Fermi level in NdNiO2, whose behaviors under Sr doping are still unclear. We perform density functional theory calculations of supercell Nd1-xSrxNiO2 to systematically study the evolution of its electronic structure at different doping levels. Our results show that a relative shift occurs between the Nd 5d and Ni 3d bands with Sr doping, deviating significantly from the commonly adopted rigid-band approximation for studying doped compounds. In addition, the relative positions of O-p bands rise with respect to the Fermi level when the Sr concentration increases, resulting in a reduced charge transfer gap. We further estimate the hole concentrations on each band and Hall coefficients, and discuss their relevance to recent experiments. Copyright (C) 2021 EPLA

Automated summary

Density functional theory calculations reveal that a relative shift occurs between the Nd 5d and Ni 3d bands with Sr doping in Nd1-xSrxNiO2, while the relative positions of O-p bands rise with respect to the Fermi level, resulting in a reduced charge transfer gap.