Exact solvable model of coupled supersymmetric t-J chains

An exact solvable model of the coupled supersymmetric t-J chains interacting via the spin exchange interaction is proposed and solved by the means of the nested Bethe ansatz. It is shown, that in addition to the direct spin-exchange interaction an effective interaction between fermions of different chains called as “an effective attractive hard-core interaction” is realized in the model. The critical exponents describing asymptotic behavior of the correlation functions are calculated using the Bethe ansatz equations and the finite-state scaling analysis in conformal field theory. It is shown that the two-component Tomonaga-Luttinger liquid with the dominating correlations of fermion pairs is realized in the low-density region. This non-traditional behavior of the correlation functions is realized due to the effective attractive hard-core interaction between particles.