Structure and dynamics of carbon, silicon, and hydrogen complexes in AlAs, GaAs, and ${\mathrm{Al}}_{\mathit{x}}$${\mathrm{Ga}}_{1\mathrm{-}\mathit{x}}$As

The results of a comprehensive Green’s-function calculation are reported for the structure and dynamics of the amphoteric behavior of silicon {${\mathrm{Si}}_{\mathrm{Ga}\left(\mathrm{Al}\right)\mathrm{}}$,${\mathrm{Si}}_{\mathrm{As}}$}, and the acceptor nature of beryllium and carbon {${\mathrm{Be}}_{\mathrm{Ga}\left(\mathrm{Al}\right)\mathrm{}}$,${\mathrm{C}}_{\mathrm{As}}$} impurities in GaAs, AlAs, and ${\mathrm{Al}}_{\mathit{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathit{x}}$As. Impurity vibrational modes are studied for (i) the nearest-neighbor ${\mathrm{C}}_{\mathrm{As}}$-${\mathrm{Al}}_{\mathrm{Ga}}$ pairs (${\mathit{C}}_{2\mathit{v}}$ symmetry) in ${\mathrm{Al}}_{\mathit{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathit{x}}$As (for x<0.04), (ii) the second-nearest-neighbor {e.g., ${\mathrm{C}}_{\mathrm{As}}$-Al(Ga)-${\mathrm{C}}_{\mathrm{As}}$; ${\mathrm{Si}}_{\mathrm{Al}}$-As-${\mathrm{Be}}_{\mathrm{Al}}$} pairs (${\mathrm{C}}_{2\mathit{v}}$ /${\mathit{C}}_{\mathit{s}}$ symmetry) in AlAs (GaAs), and (iii) the passivated H-${\mathrm{C}}_{\mathrm{As}}$ complexes in GaAs and AlAs. Comparisons are made with the existing experimental and theoretical data.