New O(3) transition in three dimensions

Abstract

A three-dimensional lattice of Heisenberg spins with nearest-neighbor interactions is studied by numerical simulation under the constraint that no free topological singularities (hedgehogs) are allowed. Only nearest-neighbor pairs of oppositely charged hedgehogs are permitted in the sum over configurations. A disordering transition with exponents different from the usual Heisenberg transition is found and tentatively identified as a pure spin wave disordering transition.