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Spin-gap phase in the extended t-J chain

Yu-Wen Lee·Yu-Li Lee
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Abstract

We study the one-dimensional deformed $t-t^{\prime}-J$ model in terms of the continuum field theories. We found that at low doping concentration and far away from the phase separation regime, there are two phases: the Luttinger liquid and the Luther-Emery liquid, depending on t'/t<(t'/t)_c or t'/t>(t'/t)_c, where (t'/t)_c>0. Moreover, the singlet superconducting correlations are dominant in the Luther-Emery liquid.

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Yu-Wen Lee, Yu-Li Lee. 2004-12-08. Spin-gap phase in the extended t-J chain. https://doi.org/10.1140/epjb%2Fe2004-00024-2

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