Werner, Philipp Hoshino, Shintaro 2020-01-07 Superconductivity with a remarkably high Tc has recently been found in Sr-doped NdNiO2 thin films. While this system bears strong similarities to the cuprates, some differences, such as a weaker antiferromagnetic exchange coupling and possible high-spin moments on the doped Ni sites have been pointed out. Here, we investigate the effect of Hund coupling and crystal field splitting in a simple model system and argue that a multiorbital description of nickelate superconductors is warranted, especially in the strongly hole-doped regime. We then look at this system from the viewpoint of the spin-freezing theory of unconventional superconductivity, which provides a unified understanding of unconventional superconductivity in a broad range of compounds. Nd0.8Sr0.2NiO2 falls into a parameter regime influenced by two spin- freezing crossovers; one related to the emergent multiorbital nature in the strongly doped regime and the other related to the single-band character and square lattice geometry in the weakly doped regime. application/pdf https://folia.unifr.ch/global/documents/308371 https://folia.unifr.ch/documents/308371/files/wer_nsm.pdf https://folia.unifr.ch/documents/308371/files/wer_nsm_sm.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1103/PhysRevB.101.041104 info:eu-repo/semantics/openAccess License undefined Physical Review B. - 2020, vol. 101, no. 4, p. 041104 info:eu-repo/classification/udc/53 Nickelate superconductors: multiorbital nature and spin freezing http://purl.org/coar/resource_type/c_6501