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arXiv · 0802.2012

Absence of Hole Confinement in Transition Metal Oxides with Orbital Degeneracy

M. Daghofer·K. Wohlfeld·A. M. Oles·E. Arrigoni·P. Horsch
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Abstract

We investigate the spectral properties of a hole moving in a two-dimensional Hubbard model for strongly correlated t_2g electrons. Although superexchange interactions are Ising-like, a quasi-one-dimensional coherent hole motion arises due to effective three-site terms. This mechanism is fundamentally different from the hole motion via quantum fluctuations in the conventional spin model with SU(2) symmetry. The orbital model describes also propagation of a hole in some e_g compounds, and we argue that orbital degeneracy alone does not lead to hole self-localization.

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M. Daghofer, K. Wohlfeld, A. M. Oles, E. Arrigoni, P. Horsch. 2008-02-14. Absence of Hole Confinement in Transition Metal Oxides with Orbital Degeneracy. https://doi.org/10.1103/physrevlett.100.066403

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