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New mean field theory of the tt't''J model applied to the high-Tc superconductors

Tiago C. Ribeiro·Xiao-Gang Wen
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Abstract

We introduce a new mean field approach to the tt't''J model that incorporates both electron-like quasiparticle and spinon excitations as suggested by some experiments and numerical studies. It leads to a mean field phase diagram which is consistent with that of hole and electron doped cuprates. Moreover, it provides a framework to describe the observed evolution of the electron spectral function from the undoped insulator to the overdoped Fermi metal for both hole and electron doping. The theory also provides a new non-BCS mechanism leading to superconductivity.

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Tiago C. Ribeiro, Xiao-Gang Wen. 2005-07-27. New mean field theory of the tt't''J model applied to the high-Tc superconductors. https://doi.org/10.1103/physrevlett.95.057001

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