2021/03/15 by Danis I. Badrtdinov, Alexander Hampel, Cyrus E. Dreyer · 10 citations
Materials Science · Physics and Astronomy · #Ab initio #Advanced Condensed Matter Physics #Anisotropy #Antiferromagnetism #Condensed matter physics #Coupling (piping) #Density functional theory #Ferromagnetism #Hubbard model #Magnetic and transport properties of perovskites and related materials #Magnetic anisotropy #Magnetic field #Magnetic moment #Magnetic structure #Magnetization #Materials science #Multiferroics and related materials #Physics #Quantum mechanics #Superconductivity #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.104.054403
published in Physical review. B./Physical review. B 104(5) (American Physical Society) · 10 pages, 10 figures
arxiv created 2021/03/15 · openalex created_date 2021/03/29 · openalex publication_date 2021/08/03 · arxiv updated 2021/08/04 · openalex updated_date 2026/08/06
We use density-functional theory calculations to explore the magnetic properties of perovskite rare-earth nickelates RNiO3 by constructing microscopic magnetic models containing all relevant exchange interactions via Wannierization and Green's function techniques. These models elucidate the mechanism behind the formation of antiferromagnetic order with the experimentally observed propagation vector, and explain the reason previous DFT plus Hubbard U calculations favored ferromagnetic order. We perform calculations of magnetic moments and exchange-coupling parameters for different amplitudes of the R1+ breathing-mode distortion, which results in expanded and compressed NiO6 octahedra. Our analysis shows that the strong competition between nearest-neighbor ferromagnetic and next-nearest-neighbor antiferromagnetic couplings determine the magnetic ordering. The inclusion of spin-orbit coupling demonstrates that the magnetic anisotropy is very small, while the magnetic moments of the short bond nickel atoms tend to zero similar to the collinear case. Finally, we show that nickelates with larger rare-earth ions display overall stronger exchange couplings, resulting in a more stable antiferromagnetic phase. Our results provide a clear picture of the trends of the magnetic order across the nickelate series and give insights into the coupling between magnetic order and structural distortions.