2023/07/22 by Chenye Qin, Qin, Chenye, Mi Jiang +3
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #Strongly Correlated Electrons (cond-mat.str-el) #Superconductivity (cond-mat.supr-con)
paper · pdf · doi:10.48550/arxiv.2307.12020
openalex publication_date 2023/07/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Infinite-layer nickelate superconductors have recently been discovered to share both similarities and differences with cuprate superconductors. Notably, the incorporation of hydrogen (H) through topotactic reduction has been found to play a critical role in their electronic structure and, consequently, their superconductivity. In this study, we utilized a theoretical approach combining density-functional theory and impurity approximation to design three characteristic multi-orbital Hubbard models representing low, moderate, and high concentrations of topotactic-hydrogen. Consistent with experimental findings, our simulations revealed that both low and high concentrations of topotactic-hydrogen induce high-spin states (S=1) that are composed by holes at dx2-y2 and dz2 orbitals and consequently the emergent inter-site hopping between dz2 to dx2-y2 is unfavorable for superconductivity. Conversely, an optimal concentration of 25% H aligns with the single Ni-dx2-y2 band picture of superconductivity in infinite-layer nickelates, demonstrating its beneficial effect on promoting superconducting behavior.