Abstract

The phonon modes of Al_xGa_1−xAs alloys have been studied with far-infrared absorption and Raman spectroscopy [1,2] and their determination of the phonon energies vs the aluminium concentration x show a larger scatter. The theoretical results are also not consistent with experimental results. Very recently, Reynolds et al [3] observed the phonon replicas in the photoluminescence (PL) spectra of an Al_0.24Ga_0.76 As alloy grown by molecular beam epitaxy (MBE). However, as they pointed out in their paper, the phonon replicas are not generally seen in the PL spectra of direct gap Al_xGa_1−xAs alloys.

© 1996 Optical Society of America