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Spin-Gap Phase in the One-Dimensional t-J-J' Model

Masaaki Nakamura
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Abstract

The spin-gap phase of the one-dimensional t-J-J' model is studied by the level-crossing of the singlet and the triplet excitation spectra. The phase boundary obtained between the Tomonaga-Luttinger and the spin-gap phases is remarkably consistent with the analytical results at the $J,J'\to 0$ and the low-density limits discussed by Ogata et al. The spin-gap phase has a single domain in the phase diagram even if the spin gap opens at half-filling. The phase boundary coincides with the $K_ρ=1$ line where the Tomonaga-Luttinger liquid behaves as free electrons, in the low-density region. The relation between our method and the solution of the two-electron problem is also discussed.

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Masaaki Nakamura. 1998-02-19. Spin-Gap Phase in the One-Dimensional t-J-J' Model. https://doi.org/10.1143/jpsj.67.717

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