SIZE EFFECTS ON THE PHONON-SPECTRA OF QUANTUM DOTS IN CDTE-DOPED GLASSES

We studied the confinement effects on the phonon Spectra of CdTe quant um dots by means of resonant Raman scattering measurements. The spectr a show clearly longitudinal optical phonons, surface phonons and some of their overtone combinations. We show that the scattering due to sur face phonons increases as the quantum dot size decreases. The results are obtained by tuning the laser excitation energy to resonance for qu antum dots of different sizes inside the broad size distribution in Cd Te-doped glasses. (C) 1996 American Institute of Physics.