Double exchange model in cubic vanadates

Abstract

We investigate the role of the double exchange mechanism for stability of the metallic C-type antiferromagnetic (C-AF) phase, which was observed experimentally in hole doped La${}_{1-x}$Sr${}_x$VO${}_3$. The double exchange model treats localized electrons in xy orbitals as classical S=1/2 spins, which interact by Hund's exchange $J_H$ with yz/zx electrons in partly filled $t_{2g}$ orbitals. Including strong on-site Coulomb repulsion $U$ between $t_{2g}$ electrons, and using slave boson method we demonstrate that C-AF and metallic phase can be stabilized due to the specific features of the hopping in degenerate and partly filled $t_{2g}$ orbitals.

6 pages, 2 figures

References in corpus (2)

• Orbital liquid in ferromagnetic manganites: The orbital Hubbard model for $e_g$ electrons
• Effective spinless fermions in the strong coupling Kondo model