The effect of oxygen vacancies on ferromagnetism in Zn1−xMnxO thin films grown by radio frequency sputtering was investigated. The grown films at different oxygen pressures were characterized by X-ray diffraction, Hall effect, photoluminescence and vibrating sample magnetometry. The observed ferromagnetism/diamagnetism by the vibrating sample magnetometry measurement due to the variation of oxygen vacancies was confirmed by X-ray diffraction, photoluminescence and Hall results. The vacancy-mediated ferromagnetism was explained by the formation of magnetic polarons.

Vacancy-Mediated Room-Temperature Ferromagnetism in Zn1−xMnxO Thin Films. N.Gopalakrishnan, L.Balakrishnan, B.Srimathy, M.S.Kumar, T.Balasubramanian: Physica Status Solidi A, 2010, 207[9], 2180–4