title: Multicritical points in the three-dimensional XXZ antiferromagnet with single-ion anisotropy.
abstract: The classical Heisenberg antiferromagnet with uniaxial exchange anisotropy, the XXZ model, and competing planar single-ion anisotropy in a magnetic field on a simple cubic lattice is studied with the help of extensive Monte Carlo simulations. The biconical (supersolid) phase, bordering the antiferromagnetic and spin-flop phases, is found to become thermally unstable well below the onset of the disordered, paramagnetic phase, leading to interesting multicritical points.
authors: Institut für Theoretische Physik, RWTH Aachen University, 52056 Aachen, Germany.
authors: Walter
authors: W
authors: Selke
mesh_terms: D000465:Algorithms; D016880:Anisotropy; D003198:Computer Simulation; D007477:Ions / Q000737:chemistry*; D060526:Magnetic Fields; D008962:Models, Theoretical
chemical_list: D007477:Ions