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Z_2 Gauge Theory of Electron Fractionalization in the t,t'-J Model

D. Schmeltzer·A. R. Bishop
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Abstract

We consider a strongly correlated "t,t'-J" spin model with a positive uniaxial anisotropy. We show that in 2+1 dimensions, this model is equivalent to spin-charge excitations coupled to Z_2 Ising gauge fields and not to a U(1) gauge fields (as in the "t-J" model). As a result a phase of frozen Z_2 gauge fluctuations is possible, giving rise to a spin-charge-separated liquid.

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D. Schmeltzer, A. R. Bishop. 2004-09-02. Z_2 Gauge Theory of Electron Fractionalization in the t,t'-J Model. https://arxiv.org/abs/cond-mat/0402114

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