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arXiv · cond-mat/9711117

An SO(5) Symmetric Ladder

D. Scalapino·Shou-Cheng Zhang·W. Hanke
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Abstract

We construct an SO(5) symmetric electron model on a two-chain ladder with purely local interactions on a rung. The ground state phase diagram of this model is determined in the strong-coupling limit. The relationship between the spin-gap magnon mode of the spin-gap insulator and the $π$ resonance mode of the d-wave pairing phase is discussed. We also present the exact ground state for an SO(5) superspin model.

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D. Scalapino, Shou-Cheng Zhang, W. Hanke. 1997-11-13. An SO(5) Symmetric Ladder. https://doi.org/10.1103/physrevb.58.443

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