2006/06/30 by X. Ren, Xinguo Ren, I. Leonov +6 · 2 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic and transport properties of perovskites and related materials #Transition Metal Oxide Nanomaterials #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.74.195114
published as Phys. Rev. B 74, 195114 (2006) · 15 pages, 6 figures, 1 table; published version
openalex publication_date 2006/11/20 · arxiv created 2006/12/14 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/29
The electronic spectrum, energy gap and local magnetic moment of paramagnetic NiO are computed using the local density approximation plus dynamical mean-field theory (LDA + DMFT). To this end the noninteracting Hamiltonian obtained within the LDA is expressed in Wannier function basis, with only the five antibonding bands with mainly Ni 3d character taken into account. Complementing it by local Coulomb interactions one arrives at a material-specific many-body Hamiltonian which is solved by DMFT together with quantum Monte Carlo (QMC) simulations. The large insulating gap in NiO is found to be a result of the strong electronic correlations in the paramagnetic state. In the vicinity of the gap region, the shape of the electronic spectrum calculated in this way is in good agreement with the experimental x-ray-photoemission and bremsstrahlung-isochromat-spectroscopy results of Sawatzky and Allen. The value of the local magnetic moment computed in the paramagnetic phase (PM) agrees well with that measured in the antiferromagnetic (AFM) phase. Our results for the electronic spectrum and the local magnetic moment in the PM phase are in accordance with the experimental finding that AFM long-range order has no significant influence on the electronic structure of NiO.