W. Chen et al., Critical properties of spin-1 antiferromagnetic Heisenberg chains with bond alternation and uniaxial single-ion-type anisotropy, J PHYS JPN, 69(1), 2000, pp. 237-241
One dimensional S = 1 antiferromagnetic Heisenberg chains with bond alterna
tion and uniaxial single-ion-type anisotropy are studied by numerical exact
diagonalization of finite size systems. We calculate the ground state phas
e diagram using the twisted boundary condition method for D greater than or
equal to 0. The ground states of this model contain the Haldane state, lar
ge-D state and the dimer state. Using conformal field theory and the level
spectroscopy method, we calculate the D and delta-dependence of the Lutting
er liquid paraments K and the critical exponent nu of the energy gap.