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Evolution of Neel order and localized spin moment in the doped two-dimensional Hubbard model

Takao Morinari
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Abstract

We investigate effects of doped holes' hopping on Neel order in the two-dimensional Hubbard model. Semiclassical staggered moments are computed by solving saddle point equations derived from a path-integral formalism. Effects of quantum fluctuations are taken into account by the Schwinger boson mean field theory. We argue that hopping of doped holes is ineffective in suppressing Neel order compared to rapid supprestion of Neel order in high-temperature superconductors. After destruction of Neel order, the quantum disordered phase sets in. Taking the strong coupling limit in the quantum disordered phase leads to a model of spinless fermions and bosons but no gauge field interaction.

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Takao Morinari. 2003-12-29. Evolution of Neel order and localized spin moment in the doped two-dimensional Hubbard model. https://doi.org/10.1016/j.jmmm.2004.04.104

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