Raman spectra of Al<i>x</i>In1−<i>x</i>As grown by molecular-beam epitaxy

Raman study of the lattice vibrations of a ternary alloy AlxIn1−xAs on InP substrate over the whole range of compositions is reported. The Raman spectra show a two-mode-type behavior involving AlAs- and InAs-like longitudinal optical-phonon modes. The frequency of the AlAs-like mode strongly depends on the composition, but frequency of the InAs-like mode is almost independent of composition. A disorder-induced scattering by acoustic vibrations is also observed.