PHONON SIGNATURES OF SPONTANEOUS CUPT ORDERING IN GA0.47IN0.53AS INP/

Polarized Raman scattering spectra of spontaneously ordered Ga0.47In0. 53As alloys, combined with low-temperature photoluminescence and trans mission electron microscopy, are used to find a unique phonon signatur e of CuPtB-type ordering. In the Raman spectra of ordered alloys, a ne w phonon peak that is absent in the spectrum of the random alloy appea rs at 181 cm(-1). The intensity of this peak correlates with the degre e of ordering inferred from electron diffraction measurements. We prop ose that Raman scattering measurements can be used as a nondestructive probe to detect spontaneous ordering in this alloy. (C) 1998 American Institute of Physics. [S0003-6951(98)02244-X]