DYNAMIC PROPERTIES OF GA1-XINXAS SOLID-SOLUTIONS - INFLUENCE OF LOCAL DISTORTION EFFECTS

Polarization measurements on Raman spectra of Ga1-xInxAs solid solutions are performed over a wide energy range (10 cm-1 - 600 cm-1) for several concentrations (x = 0, 0.09, 0.20, 0.40, 0.53, 1). They show that this system follows the so-called ''two-mode behaviour''. The predominance of the GaAs band in the Raman spectra and the large splitting of the two longwavelength optical GaAs modes over a large range of composition are correlated to the enhancement of the coupling between the two types of oscillators by local distortion effects.