X-ray-absorption near-edge-structure (XANES) spectra of the diluted-magnetic-semiconductor system Zn1-xMnxS have been measured at the Zn LIII,II edge and of Zn1-xMxS (M=Mn,Fe,Co) at the S K edge using the total-electron-yield mode. The Zn LIII edge results for Zn1-xMnxS show a dramatic reduction in intensity of the first prominent feature, just above the edge, in the XANES spectra. Analysis of the S K-edge XANES spectra for Zn1-xMxS revealed the appearance of a pre-edge peak, having linear x dependence in intensity and assigned to S 1s photoelectron excitations to an empty narrow band of S 3p–M 3d(t2) hybridized antibonding states. The rate of peak intensity with M concentration is associated with differences in the degree of p-d hybridization of states between the transition metal and sulfur. Features above the edge are generally found to decrease in intensity with an increase in transition-metal content in the alloys. The results are consistent with more S 3p–transition metal (M) 3d(t2) hybridized states and less S 3p–Zn 4(s,p) and S 3p–Zn 3d hybridized states becoming available as the transition-metal content increases in the alloys.
Relation:
Physical Review B (Condensed Matter) 50(11), pp.7371-7377
