X-ray absorption spectroscopy of transition-metal doped diluted magnetic semiconductors Zn1−xMxO

We have investigated the electronic structure of ${\mathrm{Zn}}_{\text{1−x}}{M}_x\mathrm{O}$ $\text{(M:\hspace{0.17em}3d}$ transition metal) by x-ray absorption spectroscopy. Using configuration–interaction cluster-model analyses, electronic structure parameters have been deduced and their chemical trend is discussed. Results show that the $\mathrm{p–d}$ exchange constant $\mathrm{N\beta }$ is negative and large in cases of Mn, Fe, and Co, which is consistent with the enhancement of magnetic circular dichroism.