2017/07/16 by Di Wang, Feng Tang, Yongping Du +1
Chemistry · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Anisotropy #Anisotropy energy #Atomic orbital #Chemistry #Computational chemistry #Condensed matter physics #Density functional theory #Electron #Exchange interaction #Ferromagnetism #Magnetic and transport properties of perovskites and related materials #Magnetic anisotropy #Magnetic field #Magnetization #Multiferroics and related materials #Physics #Quantum mechanics #Spin (aerodynamics) #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.96.205159
published as Phys. Rev. B 96, 205159 (2017)
arxiv created 2017/07/16 · openalex created_date 2017/07/31 · openalex publication_date 2017/11/30 · arxiv updated 2017/12/01 · openalex updated_date 2026/08/05
In 5d transition-metal oxides, novel properties arise from the interplay of electron correlations and spin-orbit interactions. Na4IrO4, where the 5d transition-metal Ir atom occupies the center of the square-planar coordination environment, has attracted research interest. Based on density functional theory, we present a comprehensive investigation of electronic and magnetic properties of Na4IrO4. We propose the magnetic ground-state configuration, and find that the magnetic easy axis is perpendicular to the IrO4 plane. The magnetic anisotropy energy (MAE) of Na4IrO4 is found to be giant. We estimate the magnetic parameters in the generalized symmetry-allowed spin model, and find that the next-nearest-neighbor exchange interaction J2 is much larger than other intersite exchange interactions and results in the magnetic ground-state configuration. The numerical results reveal that the anisotropy of interatomic spin-exchange interaction is quite small and the huge MAE comes from the single-ion anisotropy. This compound has a large spin gap but very narrow spin-wave dispersion, due to the large single-ion anisotropy and quite small intersite exchange couplings. We clarify that these remarkable magnetic features are originated from its highly isolated and low-symmetry IrO4 moiety. We also explore the possibility to further enhance the MAE.