High-temperature ferromagnetism in Zn1−xMnxO semiconductor thin films

Abstract Clear evidence of ferromagnetic behavior at temperatures >400 K as well as spin polarization of the charge carriers have been observed in Zn 1− x Mn x O thin films grown on Al 2 O 3 and MgO substrates. The magnetic properties depended on the exact Mn concentration and the growth parameters. In well-characterized single-phase films, the magnetic moment is 4.8  μ B /Mn at 350 K, the highest moment yet reported for any Mn doped magnetic semiconductor. Anomalous Hall effect shows that the charge carriers (electrons) are spin-polarized and participate in the observed ferromagnetic behavior.

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