High-energy spectroscopic study of the III-V nitride-based diluted magnetic semiconductor Ga$_{1-x}$Mn$_{x}$N

摘要

We have studied the electronic structure of the diluted magneticsemiconductor Ga$_{1-x}$Mn$_{x}$N ($x$ = 0.0, 0.02 and 0.042) grown on Sn-doped$n$-type GaN using photoemission and soft x-ray absorption spectroscopy. Mn$L$-edge x-ray absorption have indicated that the Mn ions are in thetetrahedral crystal field and that their valence is divalent. Upon Mn dopinginto GaN, new state were found to form within the band gap of GaN, and theFermi level was shifted downward. Satellite structures in the Mn 2$p$ corelevel and the Mn 3$d$ partial density of states were analyzed usingconfiguration-interaction calculation on a MnN$_{4}$ cluster model. The deducedelectronic structure parameters reveal that the $p$-$d$ exchange coupling inGa$_{1-x}$Mn$_{x}$N is stronger than that in Ga$_{1-x}$Mn$_{x}$As.