Other TM-Doped ZnO

Saeki et al. [9] reported Curie temperatures higher than 350 Kfor V-doped ZnO films [n-type Zni x V O(% = 0.05-0.15)] with electron concentrations above 10 cm grown by PLD. They found out that only the samples with carrier concentrations as high as 10 cm showed ferromagnetism, while the insulating samples were not ferromagnetic. The transmittance spectrum for the Zno.9sV0.05O film was also measured and showed absorption peaks around 480, 560 f Ti(e ( ) and 

The results obtained in the author s laboratory [152] on ion-implanted bulk ZnO samples grown by hydrothermal technique agree well with these findings. 

Samples with Nd-Na 3 x 10 cm have exhibited RT ferromagnetism, and no magnetic ordering was found for samples with low electron density ( 10 cm ). 

Such a behavior for the material prepared by different techniques may be treated as only indirect evidence of carrier-mediated coupling. However, further investigations are needed to confirm or rule out this assumption. 

The data have been corrected only for the diamagnetic background of the substrate, measured at 350 K. The optical transparency of the thin film is demonstrated by the image in the upper left inset The lower right inset shows ZFC and FC magnetization data collected with an applied field (H) of 150 Oe. (After Ref [154].) 

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