Quantum Heisenberg antiferromagnetic chains with exchange and single-ion anisotropies

Peters, D., McCulloch, I.P.(2), Selke, W.
Institut für Theoretische Physik, Technische Hochschule Aachen,
D-52056 Aachen, Germany and (2) Department of Physics, University of Queensland, Brisbane, QLD 4072, Australia


Using density matrix renormalization group calculations, ground state properties of the spin--1 Heisenberg chain with exchange and quadratic single--ion anisotropies in an external field are studied, for special choices of the two kinds of anisotropies. In particular, the phase diagram includes antiferromagnetic, spin--liquid (or spin--flop), (10), and supersolid (or biconical) phases. Especially, new features of the spin--liquid and supersolid phases are discussed. Properties of the quantum chains are compared to those of corresponding classical spin chains.