Electronic structure of the oxide-diluted magnetic semiconductor Zn_1-χMn_χO

We have studied the electronic structure of Zn_1-χMn_χO using photoemission spectroscopy measurements and configuration-interaction (CI) calculations on a MnO₄ cluster model. It is shown that the CI calculation can give a consistent description of the photoemission and d-d optical absorption spectra of Zn_1-χMn_χO as well as those of other II-VI- and III-V-based diluted magnetic semiconductors such as Cd_1-χMn_χTe and Ga_1-χMn_χAs. The CI approach predicts that the magnitude of the p-d exchange constant in Zn_1-χMn_χO is much larger than that in Ga_1-χMn_χAs.