Dimerization and Entanglement in Spin-Orbital Chains
نویسندگان
چکیده
Spin-orbital coupling: The study of orbital degeneracy in transition metal oxides is motivated, e.g., by the large variety of spin-charge-orbital ordered phases, the possible control of the orbital degree of freedom at interfaces and heterostructures, the switching from orbital ordered to metallic phases in applied magnetic fields, and the colossal magnetoresistance. The rather complex interplay of orbital and spin degrees of freedom can be formulated in terms of spin-orbital exchange models, which are derived from more general multi-band Hubbard models. A particularly challenging system that stimulated a number of studies is the one-dimensional (1D) spin-orbital model with free coupling parameters x and y:
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