Thermodynamic Bethe ansatz for the spin-1/2 staggered XXZ-model Original Research Article

We develop the technique of thermodynamic Bethe ansatz to investigate the ground state and the spectrum in the thermodynamic limit of the staggered XXZ models proposed recently as an example of integrable ladder model. This model appeared due to staggered inhomogeneity of the anisotropy parameter Δ and the staggered shift of the spectral parameter. We give the structure of ground states and lowest lying excitations in two different phases which occur at zero temperature.