Theoretical Analysis of Electronic and Magnetic Properties of NaV${}_2$O${}_4$: Crucial Role of the Orbital Degrees of Freedom

Abstract

Using realistic low-energy model with parameters derived from the first-principles electronic structure calculation, we address the origin of the quasi-one-dimensional behavior in orthorhombic NaV${}_2$O${}_4$, consisting of the double chains of edge-sharing VO${}_6$ octahedra. We argue that the geometrical aspect alone does not explain the experimentally observed anisotropy of electronic and magnetic properties of NaV${}_2$O${}_4$. Instead, we attribute the unique behavior of NaV${}_2$O${}_4$ to one particular type of the orbital ordering, which respects the orthorhombic $Pnma$ symmetry. This orbital ordering acts to divide all $t_{2g}$ states into two types: the `localized' ones, which are antisymmetric with respect to the mirror reflection $y\to -$$y$, and the symmetric `delocalized' ones. Thus, NaV${}_2$O${}_4$ can be classified as the double exchange system. The directional orientation of symmetric orbitals, which form the metallic band, appears to be sufficient to explain both quasi-one-dimensional character of interatomic magnetic interactions and the anisotropy of electrical resistivity.

16 pages, 4 figures

References in corpus (4)

• Combining DFT and Many-Body Methods to Understand Correlated Materials
• NaV2O4: a Quasi-1D Metallic Antiferromagnet with Half-Metallic Chains
• Orbital Ordering and Magnetic Interactions in BiMnO${}_3$
• Optimized Effective Potential Model for the Double Perovskites Sr2-xYxVMoO6 and Sr2-xYxVTcO6

Cited by in corpus (1)

• First principles investigation of exchange interactions in quasi-one-dimensional antiferromagnet CaV2O4