EXAFS Studies of Nanocrystals of Zn1−xMnxO: A Dilute Magnetic Semiconductor Oxide System

Zn edge and Mn edge EXAFS studies have been performed on bulk and nanocrystals (4.7 nm) of the dilute magnetic semiconductor Zn1−xMnxO, with x varying from 0.05 to 0.5. Preliminary analysis and linear combination fitting shows that Mn replaces Zn in the bulk sample, whereas in the nanocrystal samples, with different amounts of Mn, only a very small percentage of the Mn atoms replace Zn. The majority of the Mn atoms remain on the surface of the nanocrystallites in the form of Mn oxides.