Room-temperature ferromagnetism in epitaxial Mg-doped SnO2 thin films

Abstract

The magnetic behavior of epitaxial Mg-doped SnO2 thin films prepared by radio-frequency magnetron sputtering was investigated in this work. Room-temperature ferromagnetism with the saturation magnetization of about 6.9 emu/cm3 was observed in 6% Mg-doped SnO2 samples. And the saturation magnetization decreases when further doped to 8%, while the optical band-gap increases. The room-temperature ferromagnetism was induced by the holes created by Mg on the substitutional site. Additionally, Mg interstitials and oxygen vacancies play an important role in reducing the magnetic moments.