Origin of spin-glass behavior of Zn_1-xMn_xO
Abstract
ac susceptibility has been studied for polycrystalline Zn_{1-x}Mn_xO. Stoichiometric samples demonstrate Curie-Weiss behavior, which indicates mostly antiferromagnetic interactions. Magnetic susceptibility can be described by a diluted Heisenberg magnet model developed for semimagnetic semiconductors. High-pressure oxygen annealing induces spin-glass like behavior in Zn_{1-x}Mn_xO by precipitation of ZnMnO_3 in the paramagnetic matrix.