title: Quantum J1-J2 antiferromagnet on a stacked square lattice: influence of the interlayer coupling on the ground-state magnetic ordering.
abstract: Using the coupled-cluster method and the rotation-invariant Green's function method, we study the influence of the interlayer coupling Jperpendicular on the magnetic ordering in the ground state of the spin-1/2 J1-J2 frustrated Heisenberg antiferromagnet (J1-J2 model) on the stacked square lattice. In agreement with known results for the J1-J2 model on the strictly two-dimensional square lattice (Jperpendicular=0), we find that the phases with magnetic long-range order at small J2<Jc1 and large J2>Jc2 are separated by a magnetically disordered (quantum paramagnetic) ground-state phase. Increasing the interlayer coupling Jperpendicular >0, the parameter region of this phase decreases, and, finally, the quantum paramagnetic phase disappears for quite small Jperpendicular approximately (0.2-0.3)J1.
authors.affiliation: Institut für Theoretische Physik, Universität Magdeburg, 39016 Magdeburg, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Schmalfuss
authors.forename: R
authors.initials: R
authors.lastname: Darradi
authors.forename: J
authors.initials: J
authors.lastname: Richter
authors.forename: J
authors.initials: J
authors.lastname: Schulenburg
authors.forename: D
authors.initials: D
authors.lastname: Ihle