K${}_2$Cr${}_8$O${}_{16}$ predicted as a half-metallic ferromagnet: Scenario for a metal-insulator transition

Abstract

Based on the first-principles electronic structure calculations, we predict that a chromium oxide K${}_2$Cr${}_8$O${}_{16}$ of hollandite type should be a half-metallic ferromagnet where the Fermi level crosses only the majority-spin band, whereas the minority-spin band has a semiconducting gap. We show that the double-exchange mechanism is responsible for the observed saturated ferromagnetism. We discuss possible scenarios of the metal-insulator transition observed at low temperature and we argue that the formation of the incommensurate, long-wavelength density wave of spinless fermions caused by the Fermi-surface nesting may be the origin of the opening of the charge gap.

arXiv comment7 pages, 7 figures; minor modifications; Phys. Rev. B, in press

References in corpus (7)

• Half-metallic ferromagnets: From band structure to many-body effects
• CrO2: a self-doped double exchange ferromagnet
• Transport, optical and electronic properties of the half metal CrO2
• Half-Metallic Ferromagnetism and the spin polarization in CrO${}_2$
• Model Hamiltonian parameters for half-metallic ferromagnets NiMnSb and CrO2
• Theoretical study of the electronic states of hollandite vanadate K${}_2$V${}_8$O${}_{16}$
• Spin-polarized scanning tunneling microscopy of half-metallic ferromagnets: Non-quasiparticle contributions

Cited by in corpus (7)

• Peierls Mechanism of the Metal-Insulator Transition in Ferromagnetic Hollandite K2Cr8O16
• Reversed Crystal-Field Splitting and Spin-Orbital Ordering in $\alpha$-Sr${}_2$CrO${}_4$
• Double Exchange Ferromagnetism in the Peierls Insulator State
• Structural instability and the Mott-Peierls transition in a half-metallic hollandite : K${}_2$Cr${}_8$O${}_{16}$
• Ferromagnetic Peierls insulator state in $A$Mg${}_4$Mn${}_6$O${}_{15}$ ($A$ = K, Rb, Cs)
• Computational study on the half-metallicity in transition metal-oxide-incorporated 2D g-C3N4 nanosheets
• Topological Metal-Insulator Transition within the Ferromagnetic state