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Renormalization group analysis of the spin-gap phase in the one-dimensional t-J model

Masaaki Nakamura·Kiyohide Nomura·Atsuhiro Kitazawa
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Abstract

We study the spin-gap phase in the one-dimensional t-J model, assuming that it is caused by the backward scattering process. Based on the renormalization group analysis and symmetry, we can determine the transition point between the Tomonaga-Luttinger liquid and the spin-gap phases, by the level crossing of the singlet and the triplet excitations. In contrast to the previous works, the obtained spin-gap region is unexpectedly large. We also check that the universality class of the transition belongs to the $k=1$ SU(2) Wess-Zumino-Witten model.

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Masaaki Nakamura, Kiyohide Nomura, Atsuhiro Kitazawa. 1997-08-29. Renormalization group analysis of the spin-gap phase in the one-dimensional t-J model. https://doi.org/10.1103/physrevlett.79.3214

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