From ferromagnetic to antiferromagnetic interactions in n-type Zn1-xMnxO: An electron paramagnetic resonance study
Résumé
Contradictory results concerning the formation of a ferromagnetic state in Mn doped ZnO layers have been reported in the last years. We present the results of an electron paramagnetic resonance study on homogeneous single phase n-type conductive Zn1-xMnxO (x < 0.07) thin films. Based on the observation of the existence of a narrow Mn composition range, x < 0.05, where a ferromagnetic interaction is dominant, whereas for larger x nearest neighbor antiferromagnetic interactions dominate, we propose a magnetic polaron model for the ferromagnetic Mn-Mn interaction in n-type films.