Different magnetic origins of (Mn, Fe)-codoped ZnO powders and thin films

The structural and magnetic properties of (Mn, Fe)-codoped ZnO powders as well as thin films were investigated. The X-ray diffraction and magnetic measurements indicated that the higher sintering temperature facilitates more Mn and Fe incorporation into ZnO. Magnetic measurements indicated that the powder sintered in air at 800 °C showed paramagnetic, but it exhibited obvious room temperature ferromagnetism after vacuum annealing at 600 °C. The results revealed that magnetic clusters were the major contributors to the observed ferromagnetism in vacuum-annealed Zn0.98Mn0.01Fe0.01O powder. Interestingly, the room temperature ferromagnetism was also observed in the Zn0.98Mn0.01Fe0.01O film deposited via pulsed laser deposition from the air-sintered paramagnetic target, but the secondary phases in the film were not detected from X-ray diffraction, transmission electron microscopy, and zero-field cooling and field cooling. Apparently, the magnetic natures of powders and films come from different origins.

The effects of the sample forms, fabricated methods, and process conditions on the structural and magnetic properties of (Mn, Fe)-codoped ZnO powders and films were systematically studied. The origins of ferromagnetism in the vacuum-annealed powder and PLD-deposited film are different. The former originates from the impurities of magnetic clusters, whereas the latter comes from the almost homogenous phase.Figure optionsDownload as PowerPoint slideHighlights
► The magnetic natures of Zn0.98Mn0.01Fe0.01O powders and thin films come from different origins.
► The ferromagnetism of the powder is mainly from the contribution of magnetic clusters.
► Whereas the ferromagnetic behavior of the film comes from the almost homogenous phase.