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Atomically Defined Templates for Epitaxial Growth of Complex Oxide Thin Films
Published on: December 4, 2014
Orbital ordering and magnetism in layered Perovskite Ruthenate Sr2RuO4
Hung-Lung Huang1, Horng-Tay Jeng2,3,4
1Department of Physics, National Tsing Hua University, Hsinchu, 30013, Taiwan.
Abstract:
Local density approximation plus on-site Coulomb interaction U electronic structure calculations reveal that layered perovskite oxide Sr2RuO4 exhibits the ferromagnetic (FM) half-metallic ground state, which is nearly degenerate with the antiferromagnetic (AFM) phase with a slightly higher total energy. The nearly degenerate FM/AFM total energies provide a reasonable explanation for the experimentally observed spin-fluctuation. In addition, a dumbbell-shape 4d - t2g recombined dxz - dyz orbital ordering on the Ru sublattice is obtained owing to the on-site Coulomb interaction U associated with the elongated RuO6 octahedron local structure. The discovered orbital ordering is robust against the spin-orbit interaction as well as the surface terminations. Our findings unravel the on-site Coulomb correlation as the driving force of the Ru-4d orbital ordering as well as the inherent magnetic degeneracy.
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