New examination of the magnetic properties of cobalt-doped ZnO diluted magnetic semiconductors

Olivier Toulemonde (1) , Manuel Gaudon (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

Polycrystalline Zn_1−xCo_xO diluted magnetic semiconductors were prepared within a large doping concentration range from 0.5% to 10%. Thanks to a model based on the co-existence of two magnetic populations, our analysis of the magnetization measurements brings new evidence about the competition between ferromagnetic and antiferromagnetic mean field within the ZnO diamagnetic matrix. It is a temperature activated phenomenon that supports the alignment of individual Co²⁺ ions into superparamagnetic clusters. At the same time, the refined effective number of antiferromagnetically coupled Co²⁺ ions is equal to the probability of Co²⁺ ions belonging to a dimer.

Mots clés: Magnetisms; Semiconductors; Inorganic compounds

Domaines: Matériaux

Olivier Toulemonde, Manuel Gaudon. New examination of the magnetic properties of cobalt-doped ZnO diluted magnetic semiconductors. Journal of Physics D: Applied Physics, 2010, 43 (4), 045001 (5 p.). ⟨10.1088/0022-3727/43/4/045001⟩. ⟨hal-00462354⟩