Low-temperature magnetic ordering and structural distortions in Vanadium Sesquioxide (V${}_2$O${}_3$)

Abstract

Vanadium Sesquioxide (V${}_2$O${}_3$) is an antiferromagnetic insulator below $T_{\mathrm{N}}\approx$ 155 K. The magnetic order is not of C- or G-type as one would infer from the bipartite character of the hexagonal basal plane in the high-temperature corundum structure. In fact, the Néel transition is accompanied by a monoclinic distortion that makes one bond of the honeycomb plane inequivalent from the other two, thus justifying a magnetic structure with one ferromagnetic bond and two antiferromagnetic ones. We show here that the magnetic ordering, the accompanying monoclinic structural distortion, the magnetic anisotropy and also the recently discovered high-pressure monoclinic phase, can all be accurately described by conventional electronic structure calculations within GGA and GGA+U. Our results are in line with DMFT calculations for the paramagnetic phase, which predict that the insulating character is driven by a correlation-enhanced crystal field splitting between $e_g^{\pi }$ and $a_{1g}$ orbitals that pushes the latter above the chemical potential. We find that the $a_{1g}$ orbital, although almost empty in the insulating phase, is actually responsible for the unusual magnetic order as it leads to magnetic frustration whose effect is similar to a next-nearest-neighbor exchange in a Heisenberg model on a honeycomb lattice.

11 pages, 18 figures

References in corpus (9)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Structural, orbital, and magnetic order in vanadium spinels
• Enhanced Crystal Field Splitting and Orbital Selective Coherence by Strong Correlations in V_2O_3
• Lattice Distortion and Magnetism of 3d-$t_{2g}$ Perovskite Oxides
• Approaching finite-temperature phase diagrams of strongly correlated materials: a case study for V2O3
• Magnetic structure of hexagonal YMnO3 and LuMnO3 from a microscopic point of view
• Covalent bonding and hybridization effects in the corundum-type transition-metal oxides V2O3 and Ti2O3
• How chromium doping affects the correlated electronic structure of V2O3
• Self-consistent linear response for the spin-orbit interaction related properties

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• Non-equilibrium phase precursors to the insulator-metal transition in V2O3
• Early-stage dynamics of metallic droplets embedded in the nanotextured Mott insulating phase of V${}_2$O${}_3$
• Nanoscale self-organisation and metastable non-thermal metallicity in Mott insulators
• Fermi Surface of Metallic V${}_2$O${}_3$ from Angle-Resolved Photoemission: Mid-level Filling of $e_g^{\pi }$ Bands
• Frustrated Magnetism in Mott Insulating (V${}_{1-x}$Cr${}_x$)${}_2$O${}_3$
• Imaging the itinerant-to-localized transmutation of electrons across the metal-to-insulator transition in V${}_2$O${}_3$
• Disentangling structural and electronic properties in V${}_2$O${}_3$ thin films: a genuine non-symmetry breaking Mott transition
• Stress-tailoring magnetic anisotropy of V${}_2$O${}_3$/Ni bilayers
• Ultrafast orbital manipulation and Mott physics in multi-band correlated materials
• Sub-unit cell engineering of CrVO${}_3$ superlattice thin films
• Two-dimensional honeycomb-kagome V2O3: a robust room-temperature magnetic Chern insulator interfaced with graphene