2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/228570The energy spectrum of the two-magnon bound states in the Heisenberg-Ising antiferromagnet on the square lattice are calculated using series expansion methods. The results confirm an earlier spin-wave prediction of Oguchi and Ishikawa, that the bound states vanish into the continuum before the isotropic Heisenberg limit is reached.4 pages, 4 figures, 1 tableStatistical MechanicsStrongly Correlated Electronstext