Ab initio materials design of superconductivity in d9 nickelates

Motivated by the recent theoretical materials design of superconducting d(9) nickelates for which the charge transfer from the NiO2 layer to the block layer is completely suppressed [M. Hirayama et al., Phys. Rev. B 101, 075107 (2020)], we perform a calculation based on the dynamical vertex approximation and obtain the phase diagram of RbCa2NiO3 and A(2)NiO(2)Br(2), where A is a cation with a valence of 2.5+. We show that the phase diagram of these nickelates exhibits the same essential features as those found in cuprates. Namely, superconductivity appears upon hole-doping into an antiferromagnetic Mott insulator, and the superconducting transition temperature shows a dome-like shape. This demonstrates that the electron correlations play an essential role in nickelate superconductors, and we can control them by changing block layers. (c) 2023 Author(s).

Automated summary

Motivated by recent theoretical materials design, we calculate the phase diagram of RbCa2NiO3 and A(2)NiO(2)Br(2) using the dynamical vertex approximation. We find that these nickelates exhibit similar phase features as cuprates, where superconductivity emerges from hole-doped antiferromagnetic Mott insulators with a dome-like superconducting transition temperature. This highlights the crucial role of electron correlations in nickelate superconductors, which can be controlled by modifying the block layers.