Bowing Parameters Research Articles

Modulation-spectroscopy study of theGa1−xAlxSbband structure

We report a detailed study of the ${\mathrm{Ga}}_{1\ensuremath{-}x}{\mathrm{Al}}_{x}\mathrm{Sb}$ band structure over the entire composition range. We have determined the energies, as a function of temperature, at which the direct transitions ${\ensuremath{\Gamma}}_{8}^{v}\ensuremath{\rightarrow}{\ensuremath{\Gamma}}_{6}^{c}({E}_{0})$, ${\ensuremath{\Gamma}}_{7}^{v}\ensuremath{\rightarrow}{\ensuremath{\Gamma}}_{6}^{c}({E}_{0}+{\ensuremath{\Delta}}_{0})$, ${L}_{4,5}^{v}\ensuremath{\rightarrow}{L}_{6}^{c}({E}_{1})$, and ${L}_{6}^{v}\ensuremath{\rightarrow}{L}_{6}^{c}({E}_{1}+{\ensuremath{\Delta}}_{1})$ occur, and those at which the indirect transitions ${\ensuremath{\Gamma}}_{8}^{v}\ensuremath{\rightarrow}{X}_{6}^{c}({E}_{X})$ and ${\ensuremath{\Gamma}}_{8}^{v}\ensuremath{\rightarrow}{L}_{6}^{c}({E}_{L})$ occur. A simple physical model is proposed to explain the experimental values of the ${E}_{0}$, ${\ensuremath{\Delta}}_{0}$, ${E}_{1}$, ${\ensuremath{\Delta}}_{1}$ bowing parameters. A detailed comparison is made between our results and previously reported ones.

Thermoreflectance measurements on zinc sulphide-telluride alloys

Thermoreflectance measurements of the energies E0, Δ0 and E1 have been made throughout the composition range of ZnS-Te alloys. The bowing parameters were found to be 2.8 ± 0.2 eV for the E0 gap, 0.48 ± 0.08 eV for Δ0 and 1.5 ± 0.2 eV for the E1 energy-gap. These measured bowing parameters are in good agreement with the values calculated from EPM theory.