title: Mixed Ising ferrimagnets with next-nearest-neighbour couplings on square lattices.
abstract: We study Ising ferrimagnets on square lattices with antiferromagnetic exchange couplings between spins of values S = 1/2 and 1 on neighbouring sites, couplings between S = 1 spins at next-nearest-neighbour sites of the lattice and a single-site anisotropy term for the S = 1 spins. Using mainly ground state considerations and extensive Monte Carlo simulations, we investigate various aspects of the phase diagram, including compensation points, critical properties and temperature-dependent anomalies. In contrast to previous belief, the next-nearest-neighbour couplings, when being of antiferromagnetic type, may lead to compensation points.
authors.affiliation: Institut für Theoretische Physik, RWTH Aachen University, and JARA-HPC, D-52056 Aachen, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Selke
authors.forename: C
authors.initials: C
authors.lastname: Ekiz
mesh_terms: D003198:Computer Simulation; D004574:Electromagnetic Fields; D059346:Magnets / Q000737:chemistry*; D009010:Monte Carlo Method; D044367:Phase Transition; D013696:Temperature