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Flux period, spin gap, and pairing in the one-dimensional t-J-J'-model

Alexander Seidel·Dung-Hai Lee
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Abstract

Using the factorization of the wavefunction in the t-J-J'-model at small exchange couplings, we demonstrate the connection between the existence of a spin gap and an hc/2e flux periodicity of the ground state energy. We conjecture that all spin-gapped SU(2)-invariant Luttinger liquids have hc/2e flux periodicity, and that this is connected to the fact that a gapped spin-1/2 chain always breaks translational symmetry by doubling the unit cell.

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Alexander Seidel, Dung-Hai Lee. 2004-08-24. Flux period, spin gap, and pairing in the one-dimensional t-J-J'-model. https://doi.org/10.1103/physrevlett.93.046401

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