No ferromagnetism in Mn doped ZnO semiconductors

Polycrystalline Zn1 − xMnxO was synthesized by co-precipitation method with xvarying between 0.01 and 0.10. Although X-ray diffraction patterns show a typical würtzite structure with no additional peaks for all samples, Raman spectroscopy indicates the appearance of an additional mode in correlation with the absorption edge shift observed by UV-Vis spectroscopy and which is an indicator for incorporation of Mn ions into the ZnO matrix. The magnetic properties have been studied by both EPR spectroscopy and SQUID magnetometry. Their temperature dependence follows a Curie law indicating a typical paramagnetic behavior for x ⩽ 0.05 and no indication of ferromagnetism nor antiferromagnetism.