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Critical exponents of a multicomponent anisotropic t-J model in one dimension

R. Z. Bariev·A. Klümper·A. Schadschneider·J. Zittartz
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Abstract

A recently presented anisotropic generalization of the multicomponent supersymmetric $t-J$ model in one dimension is investigated. This model of fermions with general spin-$S$ is solved by Bethe ansatz for the ground state and the low-lying excitations. Due to the anisotropy of the interaction the model possesses $2S$ massive modes and one single gapless excitation. The physical properties indicate the existence of Cooper-type multiplets of $2S+1$ fermions with finite binding energy. The critical behaviour is described by a $c=1$ conformal field theory with continuously varying exponents depending on the particle density. There are two distinct regimes of the phase diagram with dominating density-density and multiplet-multiplet correlations, respectively. The effective mass of the charge carriers is calculated. In comparison to the limit of isotropic interactions the mass is strongly enhanced in general.

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R. Z. Bariev, A. Klümper, A. Schadschneider, J. Zittartz. 1994-09-21. Critical exponents of a multicomponent anisotropic t-J model in one dimension. https://doi.org/10.1007/bf01313062

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