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Generalized hole-particle transformations and spin reflection positivity in multi-orbital systems

Mario Cuoco·Canio Noce
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Abstract

We propose a scheme combining spin reflection positivity and generalized hole-particle and orbital transformations to characterize the symmetry properties of the ground state for some correlated electron models on bipartite lattices. In particular, we rigorously determine at half-filling and for different regions of the parameter space the spin, orbital and $η$ pairing pseudospin of the ground state of generalized two-orbital Hubbard models which include the Hund's rule coupling.

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Mario Cuoco, Canio Noce. 2002-09-03. Generalized hole-particle transformations and spin reflection positivity in multi-orbital systems. https://doi.org/10.1103/physrevb.65.205108

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