X-ray near-edge structure of the II-VI group ternary compounds: Experimental and theoretical studies ofCdxHg1−xTe andCdxZn1−xTe

Measurements of the x-ray-absorption edges for ternary II-VI group semiconducting compounds ${\mathrm{Cd}}_{\mathit{x}}$ ${\mathrm{Hg}}_{1\mathrm{-}\mathit{x}}$Te and ${\mathrm{Cd}}_{\mathit{x}}$ ${\mathrm{Zn}}_{1\mathrm{-}\mathit{x}}$Te have been made for the Cd and Te L edges and the K edge of Zn. These data are compared with calculations based on electron densities of states for the conduction-band states in ${\mathrm{Cd}}_{\mathit{x}}$ ${\mathrm{Hg}}_{1\mathrm{-}\mathit{x}}$Te and ${\mathrm{Cd}}_{\mathit{x}}$ ${\mathrm{Zn}}_{1\mathrm{-}\mathit{x}}$Te for x=0.0,0.5,1.0. The calculations, based on linear-muffin-tin-orbital results, cover energies up to about 17 eV above the conduction-band edge. Both the experimental data and calculated density of states are used to analyze results for the ternary compounds in terms of a virtual-crystal model based on CdTe, HgTe, and ZnTe. Using a virtual-crystal model based on the Te ${\mathit{L}}_1$ and ${\mathit{L}}_3$ x-ray edges for CdTe, HgTe, and ZnTe, predicted edges for the ternary compounds Cd-Hg-Te and Cd-Zn-Te are compared with the direct experimental data and theoretical calculations. Results obtained in these two ways are found to be in good agreement with each other.