Critical properties of the spin-1 Heisenberg chain with uniaxial anisotropy

We use finite-size scaling to determine the critical properties of spin-1 chains with uniaxial single-ion anisotropy D. A phase diagram is obtained in the (D, Δ) plane, where Δ is the strength of the interaction in the direction of the single-ion anisotropy. Critical exponents are estimated.